brake pedal clevis adjustment

[Fldawg]

Hey guys need a little help, just finshed putting my disc brakes on the back of my truck, i also put a new booster master cyl. and 4 wheel disc prop valve on. my question is , is there a rule of thunb on the clevis adjustment on the pedal or somrthing more to it. i cut the new rod on the booster to my old booster and adjusted pedal to the top, but i dont' have much pedal travel and i'm having a hard time getting my brakes to bleed out. any help would be appreciated.