Baz............. Keep the Tbird buy a reissue Fender. My '62 RI is the best Jazz I have ever owned. I hear the new RIs coming out are even better.
Parts is parts, here's a Jazzmutt I just built with stuff I've had lying around for a few years. Fender Japan body, 'Genuine Fender Replacement' neck, DiMarzios, etc. Plays and sounds fantastic.
Anybody can build just about any Fender he wants, all sorts of vendors selling the components. Not possible with ThunderBirds.