I would first do the basic stuff..plugs, dist cap. rotor, timing, clean carb etc. and then see how it runs. The wastegate shouldnt open except under boost (its purpose is to bleed boost off after a certain level to avoid detonation).
The fact that it is a turbo does not really come into play until your accelerating and thus bulding boost. Get the car running well under part throttle conditions and then check any turbo associated problems (oiling, shaft play, exhaust leaks etc)
Ross
