you wont be dissapointed 1 bit with his service or products. I would for sure go with 3" exhaust but be aware i would go with new lifters before 3" exhaust. Also keep in mind once you get into it your going to want to replace alot of other stuff. Delete EGR, AIV, CC, TB coolant line bypass. Also youll want to replace alot of your rubber lines and such.
I hope that kind of helps you out some. As Tony said though you would have to be crazy to buy a motor from anyone else.