I'm running four Cragar 15 x 7's with 275 x 60R15's on the rear and 245's on the front. Any larger on the front and they hit on the inside and affect turning radius.
I might have room in the rear to go to 295's but would need 8" rims. With 275's you need to angle the tire out to get them on and off. Rear tread is 8.5" if I remember correctly.
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