Help Brake issue

[JrJc66]

Hello all. I have a 66 long bed c10 with 4 drum, manual brake system. I am in the processes of upgrading brake system to duel master cylinder. I have replaced the master cylinder, all brake lines, all wheel cylinders, all brake hardware, and all shoes. The issue that I am having is that I can not get the front brake to operate correctly. I bled all lines and have fluid coming out clear with no air bubbles at all for corners. Rear wheels lock up fine. Could I possibly have a bad master cylinder? Second question, is it possible to blow out the master cylinder if the push rod for the brake peddle is not adjusted correctly? Any help or insight would be greatly appreciated. Btw, good news is that I was able to test drive the truck for the first time last week after purchasing it two years ago.