When my dad bought the 67 GTX (new) it was a 4spd w/ a Dana. When he bought it back someone put an 8 3/4 in it. Instead of buying a Dana for it he just used the rear that was in the 62 poloara. Now I have done many rear swapped, narrowing, leaf spring relocations. We did our home work before the swap. The perches were never moved. The leaf springs are the same distance apart. I drove the 67 GTX since the swap & that drives fine, smooth.
