Lower hole is for factory trailing arm position, and is adjustable for up to 4 degrees of anti squat allowing more drive off of corners for better performance. Bolt on mounts allow for the use of 5 different trailing arm settings.
Rear Trailing Arm Crossmember Anti Squat For Chevy C10 GMC C15 1963-1972
Rear Trailing Arm Crossmember for Chevy C10 C10 Suburban 1963-1972 Adjustable
1971 1972 Rear Trailing Arm Crossmember Anti Squat Chevy C10 GMC C15
C-10 1973-1987 CPP Rear Trailing Arm Conversion Crossmember
Fits Chevrolet GMC C10 1963-72 Pickup Truck Trailing Arm Crossmember Anti Squat
1963 - 1972 C10 Trailing Arm Crossmember