Similar to my topic, you should find out whther an Lexus alternator would fit then tell me, hahah
Heard the auto celica is 75amps, so a 5amp increase but not entirely sure on cabling, then you cud get one of a GT4 celica they are 80amp ouput and cant see the wiring being much difference. Cant help on the Supra fitment tho, i thought generally if its the same manufacturer they have the same stud pattern, but would get a second opinion before purchase