No problem...as long as you have a good understanding of the engine
control system, good at tracing and transplanting wiring harnesses, and
swap the tranny in with it.

And of course you need to get a different driveshaft, or have one cut
down, and change the front springs for the additional weight.

Other than that... cake!

Oh, wait... is there a compatible AT floor shift for it?  Hmmm

Never mind you could buy the Stang and sell the Vic for the money to get
a good part-out V-6 (mind the compatibility over the model years)

You'd miss out on all the fun of fitting a round peg into that square
hole.

Try impossible.