Daniel
I wear lot's of hats, but gun mechanic is not one of them; thus I'm not qualified to expound upon possible trigger group differences between R and FW framed guns. That said, in a visual comparison just now between my 10-bore R framed Smith and my FW framed 12-bore Smith shows no obvious difference in the size of the trigger plate between the two frame sizes. Perhaps David Williams will chime in shortly and answer your questions, as David is indeed a gun mechanic.