i dont know where you "heard" that most turbo kits force you to remove A/C, but i can name 5 big name turbo manifold companies that will allow you to retain your a/c and have an external wastegate. in my personal opinion, if you're trying to have an efficient setup, get a tial wastegate. i guess it all depends on how fast you want to go too...

btw: rev-hard, drag, inline-pro, SFP, fmax, and max-rev. whoopsy, that's six.