This is a non-issue as I learned by coincidence. I have a 73 Ripper, the really early one with the different, more massive shaped body. Its pg was made of that single ply "tortoise" material that looks mostly black and doesn't age well, it falls apart as it has mineral content and is verdigris-prone, mine was contaminated with it (pre-owner had let that bass rot for a decade in his damp cellar as he confided to me). A replacement was necessary so I sent the original pg to Jeanie's Pickguards as a template. It got lost in the mail, but the pg maker told me he already had a pg tracing of a much later Ripper (two generations from mine, i.e. different post-1974 new body AND with the 1976 change of adjustment screws for the pups outside AND not inside the pup), should he use that? I agreed out of desparation (and asked him to leave the adjustment screw holes around the pups away as my two generations older Ripper would not need them) and this is the result, my old 73 Ripper with a new four-ply, now unblack pg that looks lovely me thinks.
It fitted perfectly. Don't be confused by the controls, the luthier mistakenly put the varitone where a control knob should have been and vice versa. I liked the way it looked, so I left it, but I could be remedied anytime. He left the dial plate away "because it looked crap" on the new pg and I agreed, but it would have fitted on there even with the 4-ply. That old one-ply stuff wast thick (just not durable).
So to answer your question. Later Ripper pgs fit early Rippers, just watch out for those pup adjustment screwholes.