If you're asking only about upgrading to AFS, I assume your car already has Xenon HIDs. In that case, a retrofit 'kit' will probably not work for you. I believe the AFS system is more than just a different low beam housing with a motor in it. I think it also requires sensors for auto leveling, beam adjustment, and some kind of connection to steering for cornering. If I'm correct (and I may not be!) this is going to be a massive undertaking.
I was searching for any DIYs on this project but didn't find anything related to the M models. I was able to find a vid that explains what AFS is and how it works.
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http://youtu.be/Cu_0G9QtAMo
As far as changing out the lens, seems people have done it but you need to know the size of the lens in order to replace it with a clear one. As usual, I found plenty of info on doing this on the G models, but nothing on the M models. I'm wondering though. Since the G and the M both use D2S bulbs, might they also have the same size lenses? Either way, you will need to take apart the new headlamp housing to change the lens. I found a vid that shows how to take the main headlamp housing apart. This guy is upgrading from halogen to a projector HID, but the procedure to dismantle is the same. You use heat to remove the cover and re-seal it with butyl rubber.
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http://youtu.be/duFXYRt_nD0
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http://youtu.be/W6UvaSYdeDo
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If you could just buy the outer cover for the headlamps, you could just remove the faded ones, change out the lens, then just install the new cover with a new butyl seal.