Your fuel pump is on the front top section of your engine. Duramaxes dont have electic pumps on pick-ups. But since you have your bed off, it would be alot easier installing an AIRDOG II or FASS system.
Your waste gate works on vacume, this goes in line and has a pin hole in it and bleeds a small amount of pressure. you get an avg of 5Lbs more boost. Too much boost over pressurizes to motor and you will blow a head gasket at very least.