GMT crystal

[georgekart]

Hello everyone, I have a question some of you may be able to help me with. I have a 2017 GMT and a 2024 GMT in my collection. And to me it seems like the 2024 GMT has AR coating underneath the crystal, whereas the 2017 doesn't. The inspection of the etched Rolex coronet seems to confirm it. Therefore, I am curious whether I can switch the crystal when I will inevitably end up sending my 2017 GMT in for service. So I have a few questions:
1) Will the 12 series GMT crystal fit a 11 series GMT?
2) How do I make sure I order the part that will have AR underneath, seeing as earlies 12 series GMTs supposedly came without AR coating underneath the crystal?
3) Do you know anywhere I could source the crystal?
I will be especially happy to hear back from Rolex certified watchmakers or perhaps someone who has already changed the crystal for one with AR coating underneath, but anyone is welcome to chime in. Before anyone claims I shouldn't do it since it'll make it a franken or will hurt the value, I don't particularly care, I don't expect I will ever sell it, so it doesn't matter and even if I do go through with it, I will keep the old crystal just in case, so I can always return it to original condition if need be. Thanks in advance, everyone.

[S.Explorer]

I've seen multiple posts with discontinued models such as the 114270 getting AR under the crystal, so I think it's quite possible that your 116710 will get one too at service.

[georgekart]

Originally Posted by S.Explorer

I've seen multiple posts with discontinued models such as the 114270 getting AR under the crystal, so I think it's quite possible that your 116710 will get one too at service.

Hmm, this might actually entice me to go RSC route down the line instead of a reputable independent. Also it's a 116713 (TT), but that shouldn't really matter for the purposes of the crystal change.

[Harry-57]

I've also been told this by my UK AD, the caveat being that a watch could get a non AR original spec crystal if still in stock. Anecdotal reports in this forum suggest that the 1267 is now getting AR at service/repair time. I advise contacting one of the UK RSCs, both are helpful.