Can i install a non turbo to turbo conversion kit in a 1990 Toyota Supra?

FYI, there will be an un-aviodable issue. regardlees if the engine can accept the turbo or not. that is an engine with a sugnificant amount of miles on it (80-125K~ subjective), capable of accepting a turbo or not, will need some refurbishing. specifically the valve seats/valves, maybe rings. all of those parts, and others have been work hardened/wear mated to each other. restoring, let alone pumping combustion pressures past oem specs will result in at least valve seat burning. likely at first turn key. rings and other components, shortly there after. minimum requirements are likely a valve re-lap. typically, more. engine mod 101.