With the new families of transmissions coming online...

Aside from $$$'s,do any of them look like candidates for
retrofit in a 03 4wd?

 

Not easily, no. The 6 speeds have dedicated transmission control modules and harnesses, which would probably swap in just fine and dandy, but your '03 PCM might think something is seriously wrong when it no longer sees any transmission values because the 6 speed's TCM is running the show now.

 

If you can figure out the computer end of it, and can get it to bolt up. Go for it.

Adrianspeeder