Should be a hard pedal,and you said pressure bleeder so trapped air is unlikely. I would start with master cylinder, and bench bleed it just because. If it has trapped air, pressure bleeding may not purge it. And you will know if its spongy in the vise.
Pedal rod allowing master to return fully?
Drum brake residual valves are 10 psi,where calipers hold back 3 psi. Dont think it will affect the pedal feel though.if wire isnt connected to prop valve, use an ohmmeter to make sure circuit isnt closed.
