Double check everything!

To avoid time-consuming bodges, don’t skimp on templating, measuring and scale drawing and remember the limits imposed by the relative inflexibility of sanitary hose. I failed to take into account the hull’s curvature below the tank and the depth of the TruDesign valve and its fittings. The bottom outlet really needed to be another 25mm away from the hull side to allow for the outlet hose to connect the bottom of the valve with the seacock. Luckily I was able to remove 20mm from each of the three hose tails making up the tank and valve fittings, reducing the overall length by 60mm, which was just enough. If that had failed, I’d have had to fit a shorter bronze valve, or just routed the outlet hose direct to the seacock.