gpz vs kz 750 camshafts

I just read on webs camshaft page that the base circles for the 83-85 gpz may be different from the other kz 750's. Does anyone know the scoop on this? Do you have to measure each set of cams before you can order a set off ebay or what. I was under the impression from past posts that all these cams were interchangable. My manual says the the cams were the same on the earlier gpz's and kz's with the compression being the only variable different. Just looking for a cheaper alternative other than buying aftermarket cams but it's not worth it if I get the wrong size base circle.:S

I read that on one of the cam builders web pages, but I have not actually seen one with a smaller base circle.

I have sold ~five sets of GPz750 cams (and now I don't have any and I need a set myself), and all of them were the same.