Help with 68 A body lower ball joint.

68 Notch Back said
I bought a lower ball joint from Autozone, it is a Duralast FA424. The mounting holes on the piece are 1/2 inch. My old holes are 5/8 inch so the new ones will not work.
Has anyone else run into this problem and how did you fix it?

68 Barracuda original slant 6 and has 10" x 2 1/2" brakes

Thanks

If your existing lower ball joint has 5/8 diameter mounting holes, they are 73-76 A body ball joints.
For that to be, your spindles have been changed over to 73-76 ones.

Early A body ball joints are 1/2 inch, for drum brakes, and are 9/16 inch for 65-72 Disc brake cars.