727 Locked up while driving causes?

Just to answer an above question, I did not have the parking brake set. Took more than a day to get around to it, but I did reinstall the driveshaft and go fiddle with the linkage to make sure it was not in park, and attempted to drive the car down the driveway. Some really nasty grinding noises are coming from underneath that were not present while in neutral, so I think it is safe to say my trans is spent:oops: .(without the driveshat, the rear tires roll fine when pushed ) For the last several months leading up to this disaster, I had been going back and forth with putting an a-833 OD in and converting everything to 4 speed, and I have a donor vehicle that a friend says I can have with all of the required stuff for the swap, except for a drive-shaft. Will I need a separate drive shaft, or will the one I have be the right length? I did not find an answer anywhere otherwise.



Thanks


Bret