Last on this. Put the tank up on the V birth board and measured. Placed there, the hose length drops to 18" top to bottom of tank, and less worry about flex. That would put the Perko 20" from the front window. Perfect location, less likely to be stepped on, as the deck widens there. A big perk, under there with a flashlight, I saw why I could not budge the flat head mounting screws that hold the safety line fixtures I want off. They go into nuts that had been painted over. Got a tool on them, broke free, so another job with a solution.