Returning to Brett's opening request, the most simple of the options is a suck through for several reasons including no need to rework the carb, still got vacuum and no fuel pressure problems. Maybe even use stock ignition.
I have done this conversion on a 250 and it has taken several years (this isn,t my day job, fortunately) to realize the errors of my ways. If cost is a problem, get a kit from Turbo City in Santa Ana, CA (I can't find the web site address), use a suck through design and use the stock exhaust manifold. The kit comes with a GM computer and a harness. They are very accomodating and will program the chip for your application. Do not use the Buick turbo, you can get more HP from carbs, ignition and kicked up compression, the compressor is completely wrong. Get the correct turbo for your application. I think Turbo City has rebuilt units. Pay the bill and get it done. It is worth it in painfull problems. Good luck.
