There are more differences between a turbo and non turbo car than most people are aware of and it's no easy bolt on job by any means. The '94 850 turbo has a different engine with lower compression ratio pistons which is needed for adding any turbo or it'll blow if you run the same stock boost. It's fuel system is also different. The '94 850 turbo trans is beefier, so your original '93 trans might not last long if you swapped engines only. Then.....(assuming you install a '94 or newer turbo engine with trans), you'll need a motronic (fuel/ignition) control unit with the complete wiring harnesses, plus an intercooler, radiator (engine oil cooler) and all it's plumbing.

All in all, you'll be far better off in the long run if you sold the '93 and just buy a '94 and up turbo 850.