Sounds like you'll have to disassemble the door and fix , clean and lube everything up. You start by removing the wing window and all of the weatherstripping. That makes the side glass real loose in the door. Just work the window out and take the regulator assembly out and rework or replace it. Grease all of the rollers up and reassemble,
Scott
If a regulator from a 63 C10 will fit, I have one if you need it.
