The difference is the proportioning valve built into the brake master. The prop valve limits pressure to the rear brakes. Disks need more pressure than drums to work properly, so a disk master may feed more pressure to your rear drums than they need, which could lead to them locking up under hard braking.
Bank 1 is passenger side. Try replacing the downstream O2 sensor first. It’s the one after the cat. “V” configuration engines have 4 O2 sensors. Inline engines (with only one exhaust manifold) have only 2 sensors.
Thanks I ended up finding some on amazon. I think they were the same as the '95 altima and sentra. They work beautifully and are installed working well. Now I just need to get 1.5" springs for the rear and finish reassembly and it is nice.