Questions first:
1. Track-only car, or does it need to be street legal? (consideration for emissions testing, title, etc.)
2. If you definitely are going to turbo/super, plan on an ECU for tuning. Different engine configs are better/worse for boost and tuning. So, definitely boosting or no?
3. Is cost a consideration? If so, the cheapest donor is probably the best.
4. Do you intend to race in a particular class? That defines a lot.