so the control arms need to be boxed from what i got in the description of the sway bar it wont work with boxed arms
4 - On some high performance models (SS, GTO, 442), the rear lower control arms are enclosed (boxed) for added strength. The #939 kit will not work on cars that are equipped with these enclosed arms. The #324 must be used on these cars or the #690 or #692 as OE replacements. The #690 and #692 are for the 1964-72 models only.
4 - On some high performance models (SS, GTO, 442), the rear lower control arms are enclosed (boxed) for added strength. The #939 kit will not work on cars that are equipped with these enclosed arms. The #324 must be used on these cars or the #690 or #692 as OE replacements. The #690 and #692 are for the 1964-72 models only.