Great !! You adapt hydro brakes. Look at pics of 2003+ brake setup, or find pics of Awk08’s setup. You can use just about any caliper as long as bleeder faces up.
If you don’t find a 03+ brake pedal you weld something onto existing.
I used a warrior master w/resi , and Cali. Banshee, Warrior, or YFZ 450 are all good choices.
FYI, you can use a floating rotor (pre 03 blasters) with any floating caliper. It’s actually easier because you don’t have to be as close.
Or you could buy a complete 03+ rear brake setup.