I am not VKB, just an owner like you, so I probably should let them answer. But from the pictures I've seen there is more than just the upside down electrical contact difference in the joystick shaft between the Mk I and Mk II. (All Mk II's are B, but I think they changed other parts too.)
Mk I dry clutch tension had a bottom adjustment method; in a quick search I can only find pics here (see pics 2 and 3 in the announcement in particular):
https://forum.il2sturmovik.com/topic/26 ... unfighter/Mk II dry clutch tension adjusts from the top only, as tightening/loosening the allen makes the square 'nut' ride up and down and alter the spring tension, seen in the image on the quick operations guide from the US site here:
http://ftp.vkb-sim.pro/Documentations/G ... -Guide.pdfI didn't realize it previously (I have the Mk II, B, from the US December 2017 allocation pre-ordered in Sept/Oct timeframe), but in that early picture it looks like the dry clutch is metal too (copper or brass? In the new ones it sure looks like Teflon or UHMW plastic. Maybe the first pictures I linked were pre-production, so maybe not.
Anyway, it looks to me like a good part of the casting itself might be different, not just one or two parts you could easily switch. Not to say it *can't* be done, but may be more parts and trouble than it's worth. You might be able to do the A/B flip itself easily...but that still won't make the base a full "MK II".