go the GTR...Thats what I am thinking of doing. But I have already spend on the car the amount I paid for it (even without a rebuild). Something you will never get back, even in a gtt when you sell...if you can sell it!!! There are a bucket load of gtst's, gtt's and even GTR's...moral of the story is...unless you are going to keep it for a long time dont waste your money on mods.
Go the GTR and mod it and keep it for the cars life...thats my plan