Just got this 93 pickup for $150.00...Needs head gasket. I also got these 20inch rims for $60! The tires are shot and I need new ones. My question is, The rim is 20x8.5 and it has 235/35/20 tires. I need some with more meat. I am practically riding on the rims, the tires have been stretched out. What tire size will fill up the wheel well without rubbing? Is it 245/45/20, 255/45/20 or ??? THe truck will not be lowered it is stock height. Can someone give me some pointers? THX.