Need to know the torque

for a 72 which is the same front end: upper-install new joint torque the bolts that hold it on the a-frame to 45 ft. lbs. then torque the ball stud as follows: 40-60 ft. lbs. plus additional torque to align cotter pin not to exceed 90 ft. lbs. never back off to align cotter pin. then install cotter pin.

I did find some mechanics who specify torque ratings, but that doesn't mean their ratings are factory specs. The manufacturer of any component determines the specs of the component. An after market ball joint is not designed by chevrolet, and therefore chevrolet cannot possibly determine how the component will perform at any given torque setting.

A ball joint nut simply hold the ball joint in place, it does not perform any other function, as does bolts for a head for example. head bolts not only hold the head on, but they compress a gasket with the right pressure to make the gasket perform correctly. Too loose and the gasket will not seal, too tight, and the gasket will be deformed and fail.

The manufacturer of the gasket determines the pressure required to make the head gasket perform as designed. Same concept with a ball joint, the manufacturer is the only entity that knows the composition of the unit and the pressure required to make it perform as designed.