big~daddy
there are several gear sets that chevy uses. your basic choices are 3.08:1, 3.40 or 3.43 to 1, 3.73:1, 4.11:1 in the 10 and 12 bolt rear end range. these are about 60'' wide and make a very good swap for AD's. That covers quite a bit from towing to freeway use.
http://www.drivetrain.com/gm8.875car.html http://www.chevytrucks.org/tech/rear_ends.htm I have disc's on the front. my rear end is from a 77 burb, 4x4, heavy duty brakes @ 2.75''x 11.032'' dia.
so after you read the chevy link you can decide. disc's are nice all the way round but do you really need them on the rear.
I have 6 lug disc up front (matches my rear) and the rear is 2-3/4'' wide brake shoes. Power master. WHAT more could you want to stop!!!!!!!
my rear axle /spring perch offset is 2-1/2'' NOT the 1 - 1/2'' the kits come @.
again my .02
