look in the 4x4wire toyota tech section. there's an article about getting the info out of your model #.
i've been bitching on the 4x4wire forums to change some stuff in their tech section because it's dead wrong. mainly like saying that '79s had 4.10 gears, and that power brakes became standard in '81 or something. '79-80 had 4.375 gears, power brakes were standard in all 4x4s and i think 2wds from at least '79(i've never even seen a hilux from the late 70s with manual brakes) etc.
i think that 4wheelparts mag copied their info off 4x4wire, because it's the same and it's wrong. get your damn facts straight, people. then again, what can you expect from a magazine that mainly caters to jeep people...