The 07 Centurion Avalanche has a 3 hard tank setup that uses a common impeller pump to fill each tank through a set of 3 sprinkler valves.
First step was to remove the engine dividers and engine hatch supports. Remove the hard tank covers and hard tanks. Remove the sprinkler valve assembly and all the fill, drain and vent hosing.
Reroute belly tank fill hose from sprinkler valve to outlet of original impeller fill pump. Cut to length and connect to pump. Beyond this, everything else remains as is for the belly tank. Faster fill rate now with the original fill pump dedicated to the belly tank.
We recycled the hard tank covers and built covers for the side swipe exhaust. This concealed them, created a divider between the exhaust and sacs and provided a perfect spot to mount the 2 new pumps.
New plumbing required a new thru-hull setup for one rear pump and a T off the original for the belly and one rear pump. The hard tanks had a drain and vent thru-hulls. We capped one and retained the other as a vent for the new sac. New .75" hose for the vent lines and 1" hose for the fill/drain lines.
New 12/2 cable run from each new pump to the helm for the pump electrical. 2 new DPDT Carling switches for the new rear reversible pumps, but retained the original switch actuators. 10GA inline fuse holders and 30A fuse connected to the helm BUS supply. Switch ground to helm ground BUS supply.