I know some have taken them apart and put fronts in place of rear, by getting an extra set. Anyway there is a way to pop the part that twists into and screws to main fixture. i think custom dynamics showed pics on how it was pulled apart, to use there LED's. Others on the forum have had pics. I just don't have links too show ya... search search...lol..
Someone in the know might have done it, and have more info