Well until I save the moneyfor my 9" rear I think I'm going to pull the gears and carrier out of a s-10. I can get the carrier and gears for $50 at the local u pull it. I went and looked today and can find 3.42 and 3.73 pretty easely of coarse they are open. I did the math and the rpm difference at 60mph is 230rpm. It should turn just over 2800rpm with 3.73 but without takng in account converter slip. Do you think the 3.73 will be to much on the street with a mild bb? Also what are some openions of a gov lock? I don't think it will hold up well and think I will be better off with an open diff.