tbi ecu not compatible?

My dilemma is whether an existing 305 computer setup in a 90 GMC pickup will still work on the 350 1989 TBI engine I have installed and am almost ready to start. Will I need to change the prom in the computer or will a recycled computer one from a junked 350 do the trick. FLASH--IT DID NOT START.

Need to change injectors, knock sensor, electronic spark control module and chip. See http://www.tbichips.com/faq.htm

//2000CAYukon