Oh trust me, it is. I did that and let me tell you...that's a load of fun, right there.

Today's update is a good one:
Jamie has agreed to take the transmission back and to refund me all charges. This news made me very happy; I'm glad to see him do the honorable thing here. We had a decent conversation via text and all has been arranged.
My old transmission is now in the hands of the mechanic and his friend the "expert". Once they've got it squared away, we'll tow the GTX back to him and the Passon unit will be removed and placed back in the crate for return; my old one will be re-installed in the car then, hopefully for good.
Fingers crossed...
Thanks to Jamie for stepping up here. Restores my faith a little bit. :-)