I need a tech on this rear end I found

805moparkid said
dont also all the 7.25 suregrip rear have the big bolt axles with different spline or is that only in the 70"s

the big bolt 7 1/4 rear,s came on light duty cars with big bolt front disk brakes, the heavy duty option was the 8 1/4 so I think that is what got the sure grip, not sure if they put them in 7 1/4 that late