compression of the carb models is higher than the turbo, pistons etc would need changed, also you will need to know wether it is a lean burn or hemi type head. lean burn heads are no good for turbo conversions. if the code on the head is SM86 then it should be fine but if its SM88 you will need to find a different head for it.
Also you will need an rs turbo sump as the carb model engine wont have an oil feed outlet to the turbocharger.