I'm trying to find out what tires to put on a Shelby (Series 1). We have 265 40ZR 18's on the front, and 315 40ZR 18's on the rear. I'm looking to change tire sizes. What would you recommend in tire sizes? I've been recommended 275 35ZR 18's for the front, and 335 30ZR 18's on the rear. Also, looking to see what brand of wheels came with the Shelby (if anybody knows).