re: #412 Dark_Falcon
No, the USA never retrofitted any Shermans with 17-pounders. A small number of M4A3s (exact number and source cite to follow) were retrofitted for the 17-Pounder, but those were refitted in the UK by Britons.
Unless I am mistaken wasn’t that the fabled Sherman Firefly? (They just released that line in World of Tanks and I am doing the currently painful grind through the Grant to get a Firefly).