A. Practical. B: Challenging but feasible. C: No, because the electronics and systems are too different. D: Just buy a used V8!
The answer is A.
Scrap it and look for a V8 project if that’s what you really want.
You should swap a V8 halfway, then sell it for cheap to another dreamer with some spare cash.
As is tradition.
It’s going to cost a lot and be a ton of work to swap it. Get rid of it and buy a V8.