Hi my carrier had this conversion done to it, here is a couple of photos you may be able to zoom in and see hope they help you out, its two pistons with one fixed end so the move out at the top and bottom of the drum,
here is a link to my photos there maybe some usefull pickys on there.
http://picasaweb.google.com/daimlermk2 the yellow hull is the one with this conversion on it sorry the photos arnt in order.
martyn