No, you can't swap the rear LSD carrier to the front, they're entirely different.
As for the wear, I'm not sure. Part of me thinks yes, it will wear faster due to the higher pressure when it's slipping. Then again, part of me things that it would be the opposite effect, it wouldn't slip as much because of the higher pressure.
Anyway, here's a good description of the process:
http://www.gordon-glasgow.org/lsdtech.html Brent