i dont know alot about the 16v engine in depth but as i understand it. the fuel injection was mechanical and there was a timing module to help make every thing tikity boo, but not as i would describe an ecu. to me an ecu is a box of tricks that controls all of the engine, i.e timing, fuel,injectors,boost and the like.
i would check the web and some magazines as i have seen this conversion done before so there must be loads of info out there. but if you keep asking questions here we will try to help you as best we can