a few guys have done just that, mounted a 7m manifold and turbo on the 5m-ge. you also have to address the fuel and the re-design of the air flow path, plus decide if you wanna go for an intercooler as well.
do a search on the net for dean anderson, or "celicasupra.com" and you should find even more info.
are you planning you come to our 8th annual summer toronto toyota supra meet this august? there will be lots of mk2's there, even 1 with a 7m-gte, or maybe 2jz by then. damon saul comes up from pa, and he likes modding the mk2 very much.
check out
www.torontosupraclub.com for all the details. some other ottawa guys are coming down and you can caravan with them. meeting them at our meet, then staying in touch back in ottawa will get you lots of info for modding that mk2, and maybe you'll even buy your own.