Ok, let's say I put on a pair of 17 x 9.5" 96 style SS rims on a 91-92 Camaro with correct backspacing and all. With normal SS tires it doesn't look like it fills the wheel well all the way on a 3rd gen, so if you bumped up the tire diameter a bit, how would you know what size speedo gears to get? Anyone follow me?