Hello there and welcome to TorqueCars, great to have you with us and it sounds like you have a really cool car.
A turbo is harder to remap, and the turbo will need oil/cooling, plus a custom exhaust header and some intake plumbing. A supercharger will not require quite so much work.
Eitherway keep the boost low or you risk detonation as the engine is running quite a high compression ratio IIRC. If you lower the compression you can go with more boost.
For nasp tuning you are looking at head work, gas flowing, 3 angle valve job, larger valves, fast road cams plus conventional breathing (intake and exhaust!)