There was a change in the hinge design in the mid seventies, but the detail of which I’m not too sure of. There is a conversion kit available... someone with more knowhow will be along to help soon!! @davidoft
You can buy a hinge pin Conversion but you will also need the correct hinges for your van, have you had the doors painted yet ?
The kit is the same, you get a small pin with 2 bigger spacers, the spacers either go into the door part of the hinge or the non door part of the hinge depending on which way they need converting
Buy the correct door is what I would do, Ive seen people damage the doors without the correct hinge tool, the earlier doors are easier to get than the later ones.
Tried that but they seem to be binding I wondered if the hinge piece that attaches to the apost is different