140 amps for $140 ('05 $), writeup is for an '85 4runner with a 22RE, but may give you some help on instaling it in your '90.

Good luck.

Al

http://www.rocketcityrockcrawlers.c...ner%20Alternator%20Upgrade%20Project.pdf

KI4Dxx
?85 Toy 4Runner: 35x12.50 BFG MTs, manual, Kenwood 2M, 140 amp alt, 26 gal aux fuel tank
'06 F-350 SRW 6.0 PSD XLT 4x4, manual, Yaesu 2m, 140 amp alt, 90 gal aux fuel tank, Air Ride air bags