89 Blazer

Got a few questions about an 89 blazer first off i completely destroyed my rear and now im looking for a lsd just wondering for a suggestion on where to find one and what brand. Second i cant use the rear from my 87 because the yoke has no splines left, so im going to buy new gears for it i was looking at a set richmond gears. Ok now that im done with the diff questions i took LT's advice and went and i got blocks now i kow i need to back out the bolts for the torsion keys just wondering where there at. And my final question what code do i need to find to figure out my gear ratio i know its a gu6 buti couldnt find the ratio for it. any help would be great thanks.

Follow the torsion bars back to where they attach half way back underneath.

There you will see one bolt on each side that you can back out to drop the front end.

Have the front end up on jack stands while you do this.