So people know-
when looking at Fuchs wheels, 6x15's (901 &911 part #'s), most 7x15's (911 part #), 8x15's, 6x16's, 7x16's and 911 numbered 8x16's all have 112mm backspacing, so the width on the 7's and 8's are all added to the outside. There are some early 901 numbered 7x15's (very rare 911R rear wheels- less than 200? made) that have the extra inch added to the inside; these should clear clear the rear inner stuff, and you can tuck more tire under the rear bodywork. Or take a pair of 15x6's to a good wheel shop and they can add an inch to the inside, at far less than the 911R 7's sell for (if you can find them). The same can be done to the 16x6's.
There are some 16x8's with a 951# that are slightly different than the 911 numbered 8's (off of 944's?); these have 125mm (1/2" more) instead of 112mm backspacing, and as such are only 1/2" wider on the outside than the 911 numbered 7's. If you have inside room these would be worth finding. Al