Believe me, I'm on your side. Just check that axle to be sure the flange is true. I don't want to see your trans end up like mine did. You cant tell by just looking at that picture but the tail shaft stayed bent about 1/8". Like Crackedback said "All it takes is once".
By the way, many years ago, I broke an automatic trans when a ring gear let go and know of 2 others who took out transmissions because of problems that started in the driveline. I will look forward to the results of your test...