I'm sure all V8's, ZT/R75 Mk1 & Mk2, are identical in respect of acceptable wheels, hub dimensions, clearances etc. as you suggest, David.
However there certainly are differences between V6's and V8's, as well as between front and rear of the V8's.
Even 17" Serpentines from a V6 will actually (just) fit on the rear of a V8, but not on the front, strangely. Appears to be the calliper causing the problem.
I drove a few miles (not enthusiastically!) with a pair of 17" Serps on the back when delivering two Vortexes to the refurb shop; looked mighty odd, but didn't feel odd at all!
The only safe answer for 17's would be the Star Spokes though I think. A space-saver I use on a V6 certainly did not fit the V8, front or back.
David