Newton’s Division served as a member of the Sixth Corps in the Army of the Potomac. The division was commanded by Frank (Francis) Wheaton (May 8, 1833 – June 18, 1903), a career military officer in the United States Army during the American Civil War and Indian Wars. On November 29, 1862, Wheaton was promoted to brigadier general of volunteers and placed in command of the 3rd Brigade (62d NY, 93d Pa, 98th Pa, 102 Pa & 139 Pa), 3rd Division, VI Corps. His brigade, under the command of Colonel David J. Nevin of the 62nd New York, was the only brigade of the VI Corps to see action on the afternoon of the second day of the Battle of Gettysburg after completing a forced march of approximately 30 miles from Manchester, Maryland that day. At Gettysburg he commanded the 3rd Division while its commander, Maj. Gen. John Newton, temporarily commanded the I Corps, in place of John F. Reynolds. Wheaton was promoted to brevet major general on April 3, 1897 after the retirement of Major General Thomas H. Ruger and retired one month later on his 64th birthday on May 8. Wheaton died in Washington, D.C., of a brain hemorrhage, and was buried in Section 1, Grave 131-A of Arlington National Cemetery.
The Wheaton's US Division Tablet, also known as the Newton's US Division Tablet, is located on Sedgwick Avenue, on the right or east side when traveling north. This site is less than .1 mile away from the United States Avenue Intersection, after which this road then for some reason becomes Hancock Avenue. I suppose they ran out of road to name after Generals so they had to share. Parking is available at an enlarged shoulder just to the rear of this monument, on the opposite side of the road, directly across from the Torbert's U.S. Regulars Brigade Tablet. 
This area is one way so parking is a snap anyways. Be sure to keep vehicles off the grass or you will be ticketed by park police. I visited this monument on Thursday, July 5, 2012 at 5:14 P.M. I was at an elevation of 547 feet, ASL. I used a Canon PowerShot 14.1 Megapixel, SX210 IS digital camera for the photos.
Draw the Sword, with descriptive help from the NPS site, offers the following description: Monuments are rough-hewn monoliths, 4 feet 2 inches x 2 feet x 7 feet in height, consisting of Winnsboro, South Carolina granite. Bronze inscription tablet, 3 feet 8 inches x 3 feet 6¾ inches, is affixed to the polished face of the monolith. Corps insignia, a bronze Maltese Cross, is excised & polished at top of tablet. One of 22 Union division monuments that describe the movements and itinerary of each division of the Army of the Potomac. Designed by E. B. Cope. The Greek cross symbol of the Sixth Corps appears at the top of the tablet, just above the main inscription, on a separate piece of metal. The inscription on this tablet reads:
Army of the Potomac
Sixth Corps
Third Division
Major General John Newton, Brig. General Frank Wheaton
First Brigade Gen. Alex. Shaler
Second Brigade Col. Henry L. Eustis
Third Brigade Col. David J. Nevin
July 2. Arrived about 2 p.m. and late in the day marched toward the north slope of Little Round Top. Third Brigade with Second Brigade First division went into action at sunset on the right of First Brigade Third Division Fifth Corps on the northwest slope of Little Round Top and the combined force drove the advancing Confederates back down the slope across Plum Run marsh and a hundred yards up the slope beyond. First and Second Brigades were in reserve on the slope beyond. First and Second Brigades were in reserve on the northeast slope of Little Round Top.
July 3. First Brigade was ordered to the left and at 8 a.m. to the support of Second Division Twelfth Corps on the right. Second Brigade was sent to the right centre to report to Gen. Newton. The Third Brigade remained under the command of Gen. Bartlett supporting First Brigade Third Division Fifth Corps in the vicinity of the Wheatfield.
Casualties. Killed 1 officer 19 men. Wounded 12 officers 136 men. Captured or missing 28 men. Total 196.
There are hundreds of non-sculpted monumentation for the various Regular Union (Army of the Potomac - Federals) units & "Regular" Confederate units engaged at Gettysburg from July 1-3, 1863. There are about 10 different variations of tablets, markers & monoliths by my reckoning. Six designs represent brigade (2), division (2), corps (2), & army headquarters (only 2), each different in a subtle way so as to distinguish between armies. Battalion/battery/advance position markers & regimental monuments for U.S. Regulars & Confederate have their own distinct design (2), bringing the total to 10 designs at the battlefield. The bronze tablets (these ones, too) were created by Albert Russell & Sons Co. of Newburyport, Mass. The granite bases which accompany the various tablets were created by the Van Amringe Company from Boston, Mass. The cast iron tablets were manufactured by Calvin Gilbert. The 1910 Gettysburg Commission report lists the awarded contracts to these companies (not Gilbert) for the tablets. All of these tablets were designed by architect Colonel Emmor Bradley Cope (July 23, 1834 - May 28, 1927). He designed pretty much every tablet for both the Union & Rebel armies, each one distinct, w/ several different varieties. He is buried in Evergreen Cemetery 
in Gettysburg, as well he should be as this park and most of the things seen here today were designed by him and as such, are his legacy. These monuments were erected just after the turn of the century during the first & beginning of the second decade of the 20th century. Each one has since been preserved or restored at least twice since the turn of the 21st century. The plaques & tablets were erected by the Gettysburg Park Commission (established by the War Dept.), after they took over the administration of the park from the Gettysburg Battlefield Memorial Association (whose funds had expired) on March 3, 1893, and whose stewardship was then transferred to the National Park Service in 1933) SOURCE The Gettysburg Park Commission is also referred to as the Gettysburg National Military Park Commission or the Gettysburg National Park Commission, to clear up any confusions, especially my own.
On October 1, 1898, the Gettysburg National Park Commission in a letter to the Secretary of War set gave recommendations for continuing the task of organizing & progressing the work of the Gettysburg National Military Park. Every November they wrote their annual report which outlined the work of the GNPC for that year. The following is an excerpt from that report relevant to this waymark. The link at the end of the paragraph will take you to the entire report. The method of marking the positions of troops on this field, as approved by the War Department, is to place the principal tablet or monument of each command at the position occupied by the command in the main line of battle, and to mark the several important positions subsequently reached by each command in the course of the battle by subordinate and ancillary tablets, with appropriate brief inscriptions giving interesting details and occurrences and noting the day and hour as nearly as possible. SOURCE
Most of the Commission reports have been digitized and can be found HERE. The initial 1893 report up to & including 1921 can be found here. 1922 to 1926 are missing & have yet to be discovered. The years 1927 to 1933 were discovered in 1996 and are also included. To my knowledge this is the most comprehensive list of documents that illustrated the development and formation of the park.
Information about these specific types of monuments:
DIVISION HEADQUARTERS MARKERS (For Union & Confederate Monuments)
Division headquarters are rectangular bronze tablets mounted on large, rectangular stones. Union headquarters have a corps or service branch symbol (like a cross, clover, star or crescent moon) as a separate bronze piece above the tablet (this one has the Greek cross), while Confederate headquarters are labeled "C.S.A." on a separate bronze piece in an oval. There are 22 Union and 10 Confederate Division markers at Gettysburg. Both markers are of similar design and were all construed of Winnsboro (S.C.), granite. Each stands seven feet in height. SOURCE & SOURCE
The Wheaton's US Division Tablet is a contributing feature to the Gettysburg Nat'l Military Park H.D. which is nationally significant under NR Criteria A, B, C & D. Areas of Significance: Military, Politics/Gov't, Landscape Architecture, Conservation, Archeology-Historic. Period of Significance: 1863-1938. The monument is designated as structure no. MN439.
From the Nomination Form:
1 of 23 Civil War US Division Markers in Park. Records movements & itinerary of 6th Corps, 3rd Division under the command of Maj. General John Newton & Frank Wheaton.
Short Physical Description:
Rough-hewn monolith, 4'2"x2'x7'H. Bronze inscription tablet, 3'8"x3'6-3/4", mounted on polished face of monolith. Polished, excised Cross Corps insignia centered above tablet.
Long Physical Description:
Located east side Sedgwick Avenue, in G. Wiekert Farm.
My Sources
1. NRHP Nomination Form
2. Stone Sentinels
3. Virtual Gettysburg
4. Draw the Sword
5. Historical Marker Database
6. Wikipedia