Dont play with B body axles--there are 3 or 4 different widths of axles to get lost in----when you replace an axle shaft you have to buy custom made-----if you go with an A body housing every axle shaft is 28 inches--(no dont use the small bolt pattern axles)-if you want to upgrade you can buy a yukon axle from randys for a little over a hundred dollars--i built a dana 60 A body width for a friend running a 70 roadrunner 440 stroker with a blower and a 833 4 speed----he has been racing the car for 3 years and the yukon axle splines have not migrated (twist) his car is pushing 750 hp-----and dont sweat the small brakes you can put your current brakes on the A body housing----or you can disc it up---8.75 or dana 60 i build only A or C body width because axles are always 28 inches or 30 inches---if you buy 10 sets at a time you get a handy discount and free shipping from randys too----bob