Steve, I don't plan on using mine either being I have a
AMNPS too. Todd and I were just interested in the engineering differences. We're curious folks.
Todd, No holes in the end of housing on either one. Maybe the 2011 model had them. I think I found the major change. Look at the pics of the tray rail below. New one now has a little "lip" to keep the tray in the housing instead of just being able to slide straight out.
OLD
NEW