I dont know of any M52s in a 2002. But I dont think mounting the motor in there would be that hard. At the very worst you'd have to get rid of the steering box, switch to a rack and fab up some custom motor mount arms. Somethings I plan on doing anyways to get the motor as low and far back as possible. Not that bad in the grand scheme of things.
The displacement limit for the class I want to run in, D-mod, is 2.99L for NA motors or a 1.5x factor for boosted motors. So I wasnt considering boosting the M52. I do think that you would probably have to modify the inner fender to clear the turbo piping. Though it shouldnt be too bad.
Yes, there is a lot regurgitation on bfc about the supposed dangers of boosting an alum M52. Yet there is a very reputable turbo kit builder out there, Technique Tuning, who is scheduled to release a kit for the e46 motors, which are of course aluminum. So unless youre planning on throwing 25+ psi at it, I think you should be fine. 12psi on a properly sized turbo on an M52 should get you 350-400rwhp, which is going to feel like the hand of God in your '02.