The Gp.2 Capri ran 4 stud wheels up to 1973 (RS2600) in 13" and 15", then in 1974 (RS3100) they switched to centrelock. I am also building a Gp.2 Capri clone, and manufacturing the BBS wheel centres at the moment which are NLA. Brakes were ATE on the original factory cars, but AP calipers were also homologated.
As Peter Mallett said, get hold of the relevant homologation docs, it is all in there in (badly photocopied) black and blue
