Yea you have to learn to do stuff yourself most of the time or else you will be paying way too much money for having someone else do something what you could do yourself. And its really hard to have low income, mod a car, and have to pay someone to do it. Especially since a lot of cases ppl over charge or dont do stuff right the first time.
Hell, ive had too many instances since ive been driving- different shops screwing me over and stuff messing up; therefore might as well do it myself and break my own stuff for free ya kno what i mean..

Id ditch the air fuel ratio gauge, and i dont think the manifold should crack because of header wrap unless its trapping moisture or something somehow, im not sure on that but ive heard of something like that before. Even then, if it lowers under hood temps and saves your hood then its worth it. A manifold is easily welded or replaced. I have a shiney heat shield from sbr that sits on top the stock heatshield, works wonders, if you dont have a cold air intake ( which is a great mod to do on our cars believe it or not.) then your filter will heat soak badly and after like 90 degs or so the ecu will pull timing 1 deg. Then like after 106 it will pull another deg... Most people with intakes in stock position, their IAT's can be up to like 130degs easily, when I did my cold air my intake is always ambient temp. Big difference in power consistency and even gained a 2psi spike from it; another lb/min of air flow probably....
The knock buzzer is great, if every dsm had one thered be less broken down cars.lol Id have to ask my friend what parts he used for the buzzer and maybe i can find part numbers, but its a simple trip to radio shack for the most part. When i find out everything more specifically ill pm you about the buzzer.