The 1990-1991 design used three transducers, one for each item (EGR, wastegate, and flapper valve). The 1992-1993 design used only two transducers... one of them controlled both the wastegate and flapper valve (the output was split, and switchover valves downstream turned each on/off), the other transducer was dedicated to the EGR valve. Weird setup, lots of hoses and fittings. I could probably be talked into selling the whole rat's nest, shoot me a reasonable offer if you're interested.

Big Ben, the cost for the actuator *should* be under $100. You also need a fitting, a hose, and some clamps but that stuff is pretty cheap. You may want to test your car by routing a vacuum line directly to the wastegate ( forcing it closed, to full boost all the time) and testing your boost pressure. If it still won't hit at least 12psi, something else is wrong. If it does go to 12-14psi (or higher), the wastegate swap should fix your problem. Just remember to put things back to normal, you shouldn't drive around with a forced-shut wastegate except for testing...!