Will S3 rear footboards fit on a GP? .... and vice versa.
Looking at the difference in the 2 sets in Sticky's book [page 170] there's very little difference and no mention if the GP boards are Italian or Indian. I'm just guessing that they're Indian and have a flatter curve designed to give extra clearance for the longer finned flywheel cowl on Indian GPs, I can't think of anything else that's different in that area between S3 & GP. So if you're running a shortened fin [or Italian] flywheel & cover then they should fit.