I am restoring a 1966 type 3 square and the lhs door was rusty and picked up a door from Gosford and the hinges are different.
Are they different from notch,square,fasty

My 67 notch had different hinges to a later square back, so I guess they did change at some point.
I recall removing the pins and using the original piece against the car with te later door.

My Notch had button head allens holding it on the body, from memory, as opposed to countersunk screws on the later?

Someone with more recent experience(20 years ago!) may chime in.