What kind of brakes do we have? Confused...

Your original lug studs were 7/16 and left hand threads on left side of vehicle. You now have 1/2 lug studs, right hand thread all around. So even the OEM tire tool had to be changed for the larger lug nuts. Looks like the spindles were swapped left to right which moves the caliper from forward to rear of the rotor. This is common practice also. Relocating the caliper provides clearance for the pre 73 model design stabilizer bar. Fluid hoses for A-body will be too short. Order the longer F-body hoses.
That large diameter vacuum booster and master cylinder likely came from the same later model donor vehicle too. Happy moparing