The plot thickens Dave!
That photo at the ATA HOF is
suppose to have been taken after his 1897 GAH at Live Birds victory using his Cashmore (with which he also won 1899) BUT Marshall thereafter was a U.M.C. rep. The 1904 Touring UMC Squad, included Marshall as Captain, R. O. Heikes, C. W. Budd, J. L. Head. T. E Hubby, W. H. Heer, J. T. Anthony, F. C. Riehl and E. D. Fulford; assisted by Frank Butler, and shot in 65 Southern Cities. The first five broke the five-man squad world's record by a score of 488X500 at Palestine, Texas.
This ad implies they all used Remington CEOs setting the 5 man record
Sadly, Fulford died from pneumonia Oct. 15, 1904
AND the U.M.C. squad and the DuPont/Winchester squad must have traveled together also - this pic is from 1905 with (left to right): Rolla Heikes, Jack Fanning, Unknown, Fred Gilbert, Tom Marshall (Captain), W.R. Crosby, W.H. Heer, Unknown
This is a good shot of what looks to be a Remington taken in 1912: Banks, Powers, Heikes, Gilbert, Crosby & Marshall from
Sporting Life March 8 1913
http://www.la84foundation.org/Sports.../SL6101017.PDF