When I installed the TK5 trans, I shortened a Ranger driveshaft to 41 inch, and attached to the Plymouth rearend, 3,9 using a aluminum adapter I made.
Coupe did ok, no vibration at 40 or 50 mph.
Later, I installed the ranger rearend, 3.73, and cut down another Ranger
driveshaft to 43.5 inch. The Coupe has a vibration starting at 40mph.
I figure my 43.5 shaft not balanced, just got lucky with the 41 inch.
Yesterday, I installed a 43 inch shaft from an Explorer I believe.
I have a vibration starting at 50mph how. I am thinking I did not do a good job on the Ranger rearend install, angle not correct. I put the angle at about 2 degree.
I was thinking also, maybe my "floating power motor mounts" have sunk, (old, and hard)...
Back to the drawing board...