The factory pickup runs thru the bottom of the hull. A through hull on the transom may or may not pick up water while under way. Of course that may not be an issue if you don't need it to work under way. Of course if you use a through-hull and a hose to the pump and you don't have a seacock, you won't be able to work on the pump of feed hose with the vessel in the water.wireline said:Installed a wash down pump on my 190 tournament, not really a big deal . Put bronze thru hull fitting through the transom below water line,put pump behind port aft jump seat above water line, had open switch @ dash ran new wires , use coiled hose that reaches the bow. all for about 250.00. Keeping on top of blood and guts sure makes end of day wash down alot eaiser.
good luck