Looking at a 5.9 Magnum engine..

http://www.moparchat.com/forums/showthread.php?t=71263&page=5

That post has lots of info on the flywheel issue. See my results on post 53.

http://www.forabodiesonly.com/mopar/showthread.php?t=178065&highlight=magnum+flywheel

This is the shorter version on this forum.

Bottom line, my results show there is a difference in balance between LA and Magnum flywheels but not likely enough to matter.