I installed a Wagner MC71258 dual master cylinder. I believe what I need is 4 residual pressure valves to maintain 10 pounds of pressure on each wheel cylinder.
Why not just crack the brake lines nuts loose and see if oil squirts out--if so it has pressure in the line
You might have a disk-drum master, I got no way to loo up the part number, maybe somebody else knows
If it does seem like each line has pressure--oil squirts out all four lines near the wheel cylinders, I would crack open each bleeder screw and let in dip bleed for awhile--while topping up the reservoir. Maybe there is air in the lines ?