imspencer2u

I have an generally original '88 v6 5 speed. I pretty sure needs an actuator unit. The one I have has part # 2507408?. Besides mounting bracket/hardware, could someone tell me the difference between my unit and say a # 25074627, # 25110835 ('90 corvette), or just about any GM unit from the '86-92? Is there a difference in vaccum signal or voltage signal sent by the engine?? I would like to use a real GM over a reproduction if I can. Will greatly appreciate being enlightened. enjoy,