Red x on post 2.
Maybe the engine shifted back enough to cause the issue.
Try jacking the rear higher than front, stands under axle.
Did you put in a new rear seal and it`s a little longer than old?
Seal was not changed.
On my Scamp I installed the driveshaft many times with front jacked up and rear wheels on the ground, so this stumped me and concerned me.
The car is on a hill (rear of car is downhill) so maybe if I do jack it up level, maybe that helps.
I was always under the impression that rear axle hanging made the distance shorter?