As Adam F said try and find some of those factory 4.88's. Search car-parts.com and/or the local boneyards. I got my rear end with 4.88's out of a '94 4runner for $250. You can find 'em for less than that if you look hard enough.
<img src="/forums/images/graemlins/patriot.gif" alt="" />

-matt

-'88 toy x-cab, SAS, chevys, gears, lockers, free tires, dented body mod.
-'87 4runner, bone stock DD

"It's OK to do stupid things, as long as you are not stupid about it."