Sorry to hear the bad news about the engine, I know you suspected it after the advice on here though.
Sounds like you've got an interesting project planned.
Certainly not an easy job, the mechanical bits and pieces shouldn't prove too much of a problem just a case of swapping the correct components over.
By far the biggest problem is going to be the configuration of the ecu's it's not just a case of swapping them over.
Before you embark on it I would suggest you look very carefully as to what's involved, then make you decision.
Russ