I got my mid 70s GJ as a frame with a good condition BB & Stronglight headset. These frames are nice for a mix & match build. I used some forged DiaCompe centerpulls that are knockoffs of the Weinmanns & they fit with a 700c Araya semi aero wheel set on Mavic hubs, so if you can't find Weinmanns, get the more common DiaCompes. I was able to trade for a bar & stem off a friend's Grand Record. Shimano 600 "leFleur" shift levers & front/rear derailleurs go well on a GJ. I used the 600 crankset for a while then switched to a Stronglight triple. Look forward to pics of your build. Don