A 1977 factory service manual FSM does not give a torque value for motor mounts to block or insulators to mount for a LA or RB however, they do have specs for a slanty which uses the same size bolts:
7/16" x 20 NF bolts for the mounts to block: 45' lb.
1/2" X 20 NC stud for the insulator to K-frame mount, nut torque 65' lb.
