No problems with a carb, I would go smaller though maybe a 390 cfm. You will need to make sure the turbo has a carbon seal though. Lock the 009 dizzy to about 22 degrees, and hang on.
The tranny is something that will be definetly needed for that HP. I ran a tranny out of a 76 super beetle and it seems it is holding up, (god knows it was pounded on)

which is the strongest stock tranny you can get. It has a single side cover, thicker webbing and a solid side cover.
What is the goal? Cruising, Racing, Street terror?
Before you spend "all" the money, go ride in either my old car, Bryan Porter's car, or Wild Thangs. The power will scare ya. A 2276 in a 1200 lb buggy is plenty......