There are a few threads in the engine & trans swap area talking about swaps into a MkIII.
TallTed started one to try & actually put info together so it could eventually be done.
Only swap to date with those was the MTX-75 into a DCT car, that helps with info. on what transmission will bolt up to the std. duratec TIVCT.
To go into an SVT would be a chore similar to the SVT into an SPI Wagon swap that was written up there recently (completed).