'85 LT230GE Master Cylinder Bleeding
 

Any suggestions on how to clear air lock in the MC?
I have tried reverse bleeding from the wheel cylinders, vac bleeding and the old pump the lever process, I have no fluid flow at all, I can feel psi at the port on the MC when I hold a finger over it and squeeze the handle, its obviously air as it doesnt move any fluid and you can feel it compress. I have replaced the MC with a known good unit, same results, so I am assuming the MC is drawing air from the lines and causing the issue with the MC? I have checked all lines, connections and washers are in place, no fluid leaks.
I tried reverse bleeding, forcing fluid from one WC to the other, then cracked the line at the junction block, then cracked the fitting at the MC, then forced fluid into MC, fluid level rises and no bubbles.