First off, these 2 things don't go together. Do you want unique or HP/ TQ? They are not nec the same.
Secondly Don't put GTP badges on it.
If you want unique, its pretty clear you have your mind made up.
If you want HP/TQ, do an LS pullout and trans. Throw a cam in while its out or do a budget turbo built. More power/tq than an L67 will get you when similarly built.
I am all for something different and unique, but if I am going to the work of a motor swap in a car like that, it is going to have power as well. Did you consider rebuilding the original motor to take boost and throwing a supercharger or turbo on it?