200r pontiac gtp trannys out.

I have 2004 pontia. Grand prix gtp full package, but
the tranny is done for. It wont go intp drive amd
thinks its in nuetral when i put it into drive.reverse
works and tap shift manual all works 1st gear is
touch while using manual tap shifters. The body
has alot of dings and dents and the inside needs
alot of work. Other then that the car is good the
engine is good and the brakes and supercharger all
good. I was wondering what i should do with it i
have a perfectly good engine and supercharger
that i want to put into another car maybe, but is it
worth it i loved the car when i used to drive it and
the heads up display was amazing. I want another
car like it but should i just buy anoth gtp or could i
buy a gt2 or gt1 and convert. How hard would that
be to do.