I have no experience with the 960 cars.

I have changed out the mechanisms on the 740's. I looked for a post I made years ago concerning what I learned but the older posts are no longer available.

There was a change in the mechanisms at some point. My memory is foggy on what I found, but I believe it was the attachment points. I think there are three studs on the mechanisms that are used to attach them to the inner panel of the door.

Something about those changed at some point but it was not a big deal. It might have been that the one of the studs was in a different location but the door already had a hole where it was needed to accommodate the different stud position.

I'm sorry I can't be more help, but thought I would respond since the post wasn't getting any action up to this point.
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Any twenty minute job is just a broken bolt away from a three day ordeal