Overzealous stopping

Air in the lines? The rear drums not adjusted properly or the drums are out of round?

I have manual brakes and I've never been "ecstatic" with them. I have replaced everything except the proportioning valve and lines from the MC to the prop valve. I also did not replace or resurface the rear drums...

These are the conclusions I've come to as I've at times felt as if my fronts stick at times after converting to disc brakes.