[1.2gees]

"Remember this, if the tranny mout is worn or torn, this will not only cause the rear to chatter, but it will also put more duty on the engine mounts"

The transaxle only hangs from it's mount, so a worn transmission mount would only (possibly) relieve stress from the engine mounts in the fore/aft direction. I don't think motor mounts are made to be more sensitive to torque in certain diretions so I wouldn't worry about this.

Noise from the rear could be internal to the transaxle, but again the CV joints should be the first things to check.
Ahmet