We are having some 3-4 shift issues with a t56. (behind a small block in a 74 240z). At first we thought it was air in the clutch system but after bleeding it several times that is ruled out. It shifts though all the gears sitting still at idle but actually driving it is almost impossible to get into 3rd or 4th. Guessing the shift fork is bent. The shift stops are all still tight btw. Any ideas?