well, the thing about physics swapping is you need to have 3 settings or some crap, i cant really think of a system to set this up with... actually i got 2:
mc norm = value, offset
mc wallwalk = value, offset (same as mc norm)
mc fly = value, offset (same as mc norm)
(you need them to all have the same value)
the other, the non default offsets whould be like 000000 or somthing, whould that work?
so you can take swap the mc norm offset and grab the one you want.