65 Barracuda Disc Brake Conversion Help Needed

The 73+ drum cars used large ball joints. They retained the small bolt pattern on the drums, but the spindles use the same ball joints as the 73+ disk spindles. 73+ A-bodies had the same UCA's regardless of brake package. That does not mean the spindles are the same, 73+ drum spindles are NOT the same as 73+ disk spindles and those brake companies should know that because there are disk conversions specifically designed for 73+ drum spindles. But the upper ball joint taper is the same, they use the same UCA.

I have heard stories of a few possible exceptions, but they are the exception, not the rule. Remember these cars are 40+ years old, just because a 73+ car has small ball joint UCA's and brakes doesn't mean it came from the factory that way. Probably just means someone swapped the disks onto their car and put the 67-72 brakes on the parts donor to keep it rolling. A lot can happen in that amount of time. Old drag racers used to swap disks to drums because they thought they had less rolling resistance too.

If you're not sure, measure the taper diameter for the ball joint.