I bought the wrong transmission for my 66.

Those are easy to fix problems and cheap too.

What cannot be fixed in that trans is the wide 1-2 split. If that is NOT your complaint, then I would just fix it. If I lived next door, I could probably fix you up in a couple of hours, if the trans was on the floor and clean.
The 1-2 seems to be normal, although at times when coming to a stop light, with the clutch in, it's difficult to put into 1st gear unless I goto 2nd and then it will fall right into 1st with no problem. When taking off, 1-2 shifting is normal, third has that "crunch" whether upshifting or downshifting into that gear and 4th has the howl and a vibration I was speaking of in another post. So I need to just get the car on ramps and remove it. Thank you for your knowledge.