I added the cross-shelf in the v-berth and utilized the existing pin-rail from the existing ledges, as you can see in this photo.  The "cutout" allows for the 13" ac/dc TV to be viewed (not shown).  I picked up the radiused, pin-rail corners off a discount table for $1 each.  Shelf is melamine coated, particle-board, from Home Depot.  The shelving material was experimental and has proven to be excellent!  The teak, front edge trim stiffens the shelf:

At the same time, I also added shelf material onto the molded ledge and repositioned the pin-rail from the fiberglass ledge to the new shelf.  Makes for a wide enough place to store clothing and books:

Bob        '94 Cat-Morgan 38cc #44 "LaBoo iv

                 '83 Cat 30 TMBS   #2988  "LaBoo"
                 Vancouver, B.C. <bob@laboo.net>