So with this "EFI" are you looking at the ECU just controlling air/fuel ratio, ala the raft of carb replacement systems out there today or bumping it up to the ECU's that control spark, too? I'm a neophyte with EFI but to me the beauty of the system is having both the air/fuel map and the spark map, where you take all of the guesswork out of what your fuel and your spark timing are doing across the range of rpms.
There's almost a cult following of seat of the pants EFI guys using the likes of the MegaSquirt DIY systems, and I really respect them for their knowledge and ability to adapt pieces & parts to make a great engine management system. There's also a bunch of guys out there who think they know all about EFI, but they quickly taste shoe leather when they start talking specifics. Several of the companies (FAST & Holley for two) sell universal EMS controllers stand alone, laptop interface and capable of interfacing with just about anything you can imagine, like drive by wire throttle input.
No reason why what you're talking about can't work, IMHO, as long as you're prepared to work through some details as you go along and enjoy the challenge of making something from nothing. I'd say "Do It!!", but only if you plan to document your progress here!!

Sorry for the long winded reply, too....