just about every post on stage zero says which parts should be replaced, and some even give info on what sites you might find them, however nobody ever says which brands to look at, what worked well for them... yada yada. i'm currently looking at O2 sensors and there are quite a few brands (bosch, sng...). there are also some universal ones that come with different amounts of wires (2-wire, 3-wire, and 4-wire: i'd imagine i'd get the 4-wire as there are 4 wires that go to my O2 sensors, but which are which?) i have the same problem with fuel pumps, i see a hella pump for $126 and a bosch for $278. what the heck is the difference? what have people tried? thoughts?