I know this may not help you with where your at right now, however on my 67 up A bodies i break off the star washer looking damn hinge retainers on dissassembly, then i drill the pins for small cotter pin, and use a washer and cotter pin to retain the hinges in place.
sounds like good way to do it. but like you say won't help my immediate problem. I;m sure those little star washer retainers after 5o years get pretty thin!!
I think I will get couple 1/2 in lock washers and stick the mig head in there and tack weld.