[my67chevytruck]

71-72 had discs, Richard as long as you have a disc/drum proportioning valve your golden if you swap in a 71/72 xmember. to add more confusion, you could also swap in a 73-87 front xmember. for the rear you could get a 71/72 and it will bolt right in, if you dont want to mess with changing the rear, they make conversion axles that will give you the 5 lug rear...

we went the '72 route for my son's truck after speaking with Jesse on the subject.....

best of luck.