69 cuda wheel size

I just went out and took a look. 255-60-R15 Radial TA's. But, the pass side is only about 1/8" from the rear spring on the rear. Be sure to check yours carefully before going for the 4.25" offset. 4" may be safer if the rear axle is not assembled perfectly or if one of your spring clamps happens to be right where the tire is closest. Tom