65 C10 Brakes Question

[Daron Craig]

On my 65 I installed a new master cylinder. I bench bled it first. I ran all new hard lines. There are 3 soft lines one at each front wheel, and one that transitions from the hard line along the passenger side frame to the a tee that goes to each rear wheel with hard line. Trying to bleed the system I cannot get the rear to flow. It moves fluid, but does not come out like the front. I cannot get a good brake pedal feel either. Am I missing anything?