ok so a am about to start modding a 2000 gtp and here are the mods i plan on doing FWI, ssca headers, 104 autolites, 180* T-stat, ported TB, ported SC inlet and outlet, 1.9 rockers and an aeroforce scan guage. so my questions are should a vendor pcm be a good choice of so which one? i have had so many ppl tell me different things. OR should i go a custom tune? also at what point in the modding process should i get a pcm/tune?