How is the hinge pin? They wear but can be replaced with new oversize pins. Heart of England sell the pins and give you a drill to resize the hinges. Trouble is you need the hinges off the car.
Does Gomog give a method? I think the screws are machine screws with captive thread inserts in the pillars. If they have loosened then it is a more awkward job sorting them out. Even drilling the screws out will be tough if they spin.
I've just taken my hinges off as the slop was in the hinge pin. Mine's a '74 so probably different to yours. Bolts go through the A pillar and the door frame (oddly lowest bolt in the door is actually a woodscrew!). No captive nuts but a steel plate as reinforcement.
You won't be getting any oversized hinge pins from H of E as they are out of stock and factory is closed. Won't be available anytime soon, possibly next year as when the factory re-opens , hinge pins are low down on the priority list!