Headers and fuel pump are a must. I don't know much about the ATI but the Vortech kit comes with a FMU, so your stock injectors will be fine with thier kit. If for some reason you decide on bigger injectors(for whatever reason) don't forget you will have to recalibrate that Pro-M(the fmu is also calibrated for specific injectors). You should have gotten those rear gears long before now, that was my very first mod(not counting air filter and tune up).
I'd say headers, fuel pump and gears are most important at this stage.
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Rick
My 89lx(updated 7/20/2001)
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