Do you currently have the 12 bolt, or is it a 10 bolt. If it's a 10 bolt you can swap the center section for a 4.10 gear like GMCPanel described. I think you can do the same if you have a 12 bolt. Another option is to get a 14 bolt corporate from a late model, and swap the spring and shock mounts. With the 14 bolt 3.73 gears are were standard, 3.42 are available in the newer ones.


Fred
52 3600
69 C-10