For the Act of Congress, see H.R. 1044, Bills and Resolutions, House of Representatives, 39th Congress, 2nd Session, Jan. 27, 1867, Read twice and referred to the Committee on Pensions. An Act For the relief of John Gray, a revolutionary soldier, accessible online via Library of Congress, Digital Collection URL https://memory.loc.gov/cgi-bin/ampage?collId=llhb&fileName=039/llhb039.db&recNum=5497.
in addition, Findagrave.com has a nice memorial page for John Gray to include photos of him, monuments to him, grave marker in Noble County Ohio, and two newspaper articles that was graciously shared by someone other than me.