4000S transmission found-now what?

[Sprint]

OK, I have located a replacement automatic transmission 
for my 1987 4000S.  I am buying only the transmission part 
that hangs on the rear since there is no problem with the 
diff unit.  Here's my next question.  Is it possible to 
separate the 2 units and replace the auto trans unit 
without dropping the entire transaxle out of the car?
The transmission was damaged by the DPO running it out 
of fluid (I think).  Should I be concerned about the torque 
converter and governor being damaged?  
Thanks,
Dave