Phaze2 Mike

Well guys, instead of the greddy kit, i think i am going to piece a kit. I am not going to cut corners, and want to do it right. I am looking to boost 5-8 psi, and dont wanna skimp on anything. I know theres alot of sites on building your own kit, but what should i build around. Like, should i start with my turbo (prob a t3 or similiar size) and then look for the manifold, downpipe and wastegate, or start with the manifold and then find a turbo that fits? any advice be great