[454HO]

Just last week I picked up a non-posi 3.42 rear end from a recycle yard for $100. It was from a '88 Suburban that had just come in to be stripped. A Powertrax locker is about $330 from Summit and it installs easily at home with no special tools required. And for disc brakes, there are several complete conversion kits available in the $350-$400 range, or you can just get a set of mounting brackets for the Eldorado calipers and source all the rest of the parts yourself.