Fully adjustable upper A-arms for ‘67 Barracuda

Define "fully adjustable" for us. The factory upper arms are "fully adjustable". They just don't have the range of caster adjustment some of the aftermarket arms do. Do we assume you mean arms with adjustable heim joints? That's gettin mighty fancy for a street car. What are you intentions with the car?
The factory upper a-arms are not adjustble, just the mounting bolt location is. I have -3 degrees of caster as my car is set-up with offset bushings and trying for the most caster.

The better question is, why the desire for fully adjustable UCA’s while retaining the small ball joints? Since that will likely mean retaining the factory brakes and small bolt pattern, which means probably not running really wide tires, which reduces the need for a fully adjustable UCA anyway.

But if you really wanted fully adjustable and wanted to keep the factory small ball joint spindles, it might be worth reaming those spindles to take a large upper ball joint so you could use the SPC’s.
I am running the factory 4 piston disc set-up & do not want to get rid of that, may just have to ream out the upper mount.

SPC Gen I and Gen II and Hotchkis.

@BergmanAutoCraft can set you up with the SPC options. You can also add taller ball joints at the same time with his Howe options.
I will check those SPC arms out and I am really curious about the taller bolts, that could really help alleviate some of my caster issue.