For Big Block Fords specifically, this 7/16" stud girdle adjusting nut is threaded through the full length.
Stud Girdle Adjusting Nut for Big Block Ford w/ 7/16" Stud
Adj Nut Big Block Ford w/ 7/16" Stud
4511-1 - Stud Girdle adj Nut, 7/16
COMP Cams Stud Girdle Adj Nut 7/16
Engine Rocker Arm Adjusting Screw
Stud Girdle adj Nut, 7/16
RockerArm Adjt Screw
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