Hi Keith,
I have a 1975 GL1000 (soon to be tax exempt, yippee!) and can do my best to measure whatever I can get at, bearing in mind (no pun intended) that it is all together and working. CMSNL or DS parts lists might help to find common part numbers for bearings and perhaps yokes. Do you have the tree for the 750? I can measure the stanchion centre distance accurately. Let me know if you need measurements or pics.
Regards,
Ian