So, I'm working on fitting this '06 GMC Sierra 8.625" 10-bolt axle under my '84 Trans Am, and possibly using the matching 17x7.5" wheels, puts the outer edges 1.5" too far out. I'm thinking about that, and possibly just getting these wheels widened, when I remember that the '93 McLaren F1 used something like a 305/45R17 or 315/45R17 Goodyear Eagle on the rear.
I start with TireRack, and nothing, so I go directly to Goodyear. Still nothing. But I do find that there is an Eagle G-18 rain radial, in a 28.5" x 14.5" x 17" size. It has 14.6" of tread width, and calls for a 14.5" rim width.
Now recalling Stephen showing us how to fit an 11" rim on a stock axle, with 7" of backspacing, then correcting for my axle width and the design of these wheels, only allows me a 12.5" total.
I'm not about to mini-tub the car, but I do like those flared widebody rear fenders from www.americansportscar.com.
So, I just need to find some hub-centric 2" steel spacers with a 6 on 5.5" pattern.