Hi I am in the process of rebuilding a 55 GMC pickup. At the moment I am investigating the rebuild of the rearend. Ill be mostly cruising, so Im thinking gas mileage here. later Ill be installing a 350 and probably some kind of fuel injection vice the carb route. Im retired and trying to keep the dollar amount down. the truck has a 10 bolt in it and everyone tells me I should be looking at a 12 bolt or the 9" ford. Im sure Ill kick once in awhile,