BE CAREFUL!!!! I've got a 2006 Mazdaspeed6 which is equipped with a K04. My engine is the same 2.3L four-cylinder (turbo obviously) as the CX-7, and it's intercooled. Stock it ran about 15-16 psi of boost and I'm running around 17.5 now (still within the "safe range"). The engine came stock with forged internals as it runs 9.5:1 compression, and I would strongly recommend going forged depending on your engine's stroke and compression ratio.
Despite these various safeguards that Mazda put into place, the MZR 2.3L DISI turbo is known in Mazda-circles for throwing rods. Sooooo . . . be VERY careful about what you're doing and get properly tuned when you're done. I'd also strongly recommend staying out of boost at low revs if possible, as it's a lot of strain on the engine.
Strop is right on target with what he's saying as well. I know you're on top of this seeing as you're clearly a gearhead, but I'd hate to see things go pear-shaped as you boost your Mitsu!
Happy turbo-ing all the same!