I take it you don't have a washdown hose in the anchor locker? You might think about installing one. My H36 (later version of your 356) has one installed with the washdown pump under the forward berth on the starboard side, and the raw water line is teed off of the through hull for the air conditioning, so no additional through hull is needed. The hose goes up through the deck on the inside of the anchor locker. It is invaluable for washing the thick Chesapeake mud off of the anchor here - I wouldn't own another boat without it. You could also use it, with a longer hose in a pinch, to wash the decks down and not bite into your fresh water tank reserves.
The other consideration is power, but since I have an electric windlass installed - which I bet you do - that's not a problem at all. The pump is wired to the windlass power, so your wire run is pretty short.
Its all easily accessible if you pull out the mattresses and pull up the inspection/access boards already there, and then roll on your back and take off the cover of the box that is at the foot of the v-berth and you'll see the windlass and wiring all within arms reach.