In order to achieve this I made a little tray for the receiver and cut the bottom off a normal plastic pot to the same depth as a standard servo. Formed a liteply top and cut apertures for the servo and battery. The pot is then glued directly to the hull just behind the fin box and in theory the servo and battery should remain nice and dry. The top of the pot is then fixed in the preformed kicker well recess. The void between the top and bottom of the pot allows for good ventilation of the hull whilst the lid is off.
The pot bottom ensures everything inside stays dry