Well search isn't working for me so - Is the 1997 - 99 GS Alternator the same as a GSX and GS-T alternator ? I tried to look on autopart websites like pep boys and autozone and what not and it shows the GS uses a 90 amp alternator and the GS-T a 75 amp :/ ..anywho will the GS alt. bolt into a GS-T/GSX ?

I doubt it man, 4g63's are a Mitsu motor and 420a's are a Chrysler deal... I doubt they used the same alternator especially since you say they are of different output.

And please use the subforums next time. :)

not the same part man