The door hinges on our trucks are a well-known area for wear. Over the years, I accumulated a few spare hinges for the day when I was ready to restore my 3R6. That day has arrived, so I'm trying to pick the best hinges to use. I marked those I removed myself as to which side they fit, but I also bought a couple without any markings at all. To state it simply, the upper hinges appear to be identical, even though the parts book shows different numbers for all four hinges. The bottom ones have a 90-degree flange that bolts to the running board step, so they can be identified, left and right. But as shown in Zane's pictures, the uppers appear to be identical:
(Nice job, Zane, BTW!)
Note that the two sets of three holes in the doors are reversed L and R. One door has two holes next to each other and a third ABOVE for each hinge. The other door has the single hole BELOW the two that are side-by-side. The only reason I can think of to have built the doors that way was so that the same hinge could be used for the top of both doors. But the parts book says they're not . . . . .