[whitetop]

ET and Ansen are not the same company. You can run any wheel size and be correct. Motion ran just about every size, backspacing and probably just about every rim manufacturer selections ever made. Most common are Cragar, Ansen, International and American Racing.
Probably earlier cars (67-late '69ish)ran 15x7 width wheels in TT, slots or Cragars on the rear while later ('69ish throughout the '70's)cars mostly 15x8 1/2. The 15x8.5 slots did not really hit the market strong until really about '70. Steel wheels like Cragar came in 15x8 and 15x10.
All aluminum slots came in 15x8.5 width except 2 companies that made them 15x8. Of course they made 14x6, 14x7, 15x6 and 15x7.
Some of the Motion cars ran 15x4 Cragars or slots on the front.
Dave