I've owned 4 66'-67's and will tell you a lot depends on the ride height also. My 67' doesn't have an Alston clip (CPP subframe kit) but I'm running 18x7's up front with 215/40/18's. I adjusted the coilovers down for a slammed stance, for a car show last week and the first bump and turn I had to do, nearly took off my front wheel trim. I'm going to have to raise it up a turn or two. If the car has the wheel trim, I'd stick with a 215. An 8" will fit with the proper BS, but that much less clearance if the car is lowered. Of course Airride would solve most of this...