Wheels are Factory Reproduction C6s
Front: 18x19.5, +56mm offset, 275-35-18 tire
Rear: 18x10.5, +58mm offset with a 5/16" spacer (changing the offset to about +50mm), 295-35-18 tire
Rear OEM C6 wheels will not fit an F-body directly. Fronts will. Rears can be made to fit on a fourth gen with a 1.25" adapter and some massaging of the wheel well with a hammer. On a 3rd gen i'm sure it would prove extremely difficult, if not impossible, to make a OEM 19x10 C6 wheel fit. I would guess the front, 18x8.5 would fit though.
This 3rd gen has 18x8.5 fronts and 18x9.5 rears I believe. I'm pretty sure he said he had to "modify" the wheel wells.
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2000 Trans Am M6. Few mods. Best 1/4 mile: 13.03.... 326 rwhp, 338 rwtq
But, straight Lines are boring!