Ok for the pump, i would just spend the extra 35and get the hp walbro. Ive heard of alot of people (1 of them i know personaly) have a problem with them not sucking from the bottom of the tank. So you always have to have a 1/2 tank of it will spit and sputter. For injectors i would look around for a used set of 550cc+ sized injectors. I would shoot for 650 or larger but 550s will get you right on the line of your power. As for head studs, check extreampsi.com they have them for $100ish if it was my car, yes i would get them. Most people run to much timing and blow out hg's. If your head bolts are torque to yeald style (they have the funky drillbit look to them) then no, throw them in the trash and get new bolts, or studs. If they look like a regular bolt, fuck it, use them i reused mine like 3 times before i said fuck it and went with studs.