WTF Front Brakes?!?
Oh boy!
So those are pin type disks, found on primarily on B/E bodies but also some FMJ or R bodies. That’s not a big deal, you buy disk brake parts for an E body.
B/E body spindles are large ball joint. So, it looks to me like someone sectioned a B/E body UCA onto your A-body UCA to accomplish the large ball joint swap. B/E body UCA’s are wider so they won’t bolt on. So they grafted the ball joint end on.
Another complication could be the wheel bearings, the 70-72 B/E body spindles were different and had smaller wheel bearings than the 73+. Used to be they had a two piece rotor set up that was expensive, they make a single piece version now so I can’t tell if you have 70-72 or 73+ spindles.