Dot Over 90 Speedmaster Bezels

Disagree on the transitional watch bezel. If you see in your picture the bezel is clearly not centered so that in itself is strong evidence it is not original to the watch.

When it is said that you have the wrong bezel insert or that you should have a dot over 90 bezel insert on your model watch, what would be more correct to say is: Your model originally came with a dot over 90, it now has the Omega service replacement (or the same from a later model equivalent). Omega no longer has bezel inserts that are exactly the same as the original.
Of course a collector would prefer a watch be as originally correct as possible and this would give a premium to your watches value. Well we can't always get what we want and it makes no sense to throw the baby out with the bath water. Many of these old watches have something that is not completely original, bezel, hands, crowns. You still have a very nice model and a great watch. If a more original insert comes along you can snatch it up and replace yours.
My 2998 also needs a dot over 90 bezel and it is even harder to find as it is slightly smaller and scarcer then yours. I love it and is still quite valuable just the same, as is yours.

Hmm....

rare caseback with a DON... Curious as to the serial, might be an accidental caseback swap during a service.

What's the serial (or start if it)?