I wish you the best of luck but your looking at matching every input, gnd point, signal wire and outputs, pwm controllers for TSS, drive by wire controllers and PiD config tables As well as the loom being correct.
Or did you mean something like a universal kind of PCIII? In theory yeah you could do something like this but you'd need a unit that had the same rev limit otherwise you'll not get the mapping space.
I'm waiting for updates from Microtec mate. It looks like the F3 won't be too much longer and in theory the F4 should just be an evolution of the same ECU so I'm hoping won't be too far behind. The F3 really is the base model from which we can build every other fitting.