i got some saleen rims with a supposed centerbore of 70.5mm ... here's the thing though, I measured the center hole on the rims and i keeping getting 70mm not even a smidge off so if i get hub centric rings with a 70mm outside and 66.06 inside (closest i could find) will they fit well enough to work with a z31 ? ... is the centerbore for a z31 actually 66.06 and not 66.10 ?

 

you don't really need to worry about the centerbore as long as you can use the right kind of lug nuts.

 

such as ... the tapered conical ones

 

if that's what the wheels require, yes.