727 - Driveshaft Jammed All The Way In

Guys, I REALLY appreciate all the feedback-


1) I've been planning this swap for some time now - rebuilding the axle, purchasing new left springs etc. Part of the plan all along has been to measure for and have a correct length driveshaft built or have this one cut down and balanced, as I know that the 8 3/4 will require a shorter driveshaft. I have a local shop that is going to do that for me when ready.

2) My discovery of the slip yoke being bottomed (or close to it) out at full droop, full compression and ride height (after Mopar Tim's suggestion) led me to question whether or not some internal damage to the transmission could have taken place. It is my understanding that (and please correct me if I am wrong) that there is an overall length difference between a 904 and a 727 (Approx 3" if memory serves) - I am relatively certain this car came from the factory with a 904 which could explain why - this shaft is too long now and bottoming the slip yoke - However, when I got this car it DID have incorrect motor mounts installed - I have since installed the correct mounts and biscuits and replaced the transmission mount- perhaps that moved the motor back to its rightful place putting that pressure on the driveshaft.

3) As far as the current transmission - if I keep the 727, it will come out and be rebuilt. The presence of water in the fluid in the tail shaft housing doesn't bode well, and I can't trust that someone down the line just didn't do a quick pan drop and fluid change after having a trans cooler fail or something.

All in all - I have a pretty clear path moving forward. I appreciate the insight and hope that all have a great day.

Thanks

Edited to clarify that slip yoke was bottomed or very close to being bottomed