Which has 4 mounting feet as I recall. I sort of agree with you, that 30 looks like it could rock a bit if someone was pumping in a panic.

For what it's worth, Mike, I had an unusual requirement, I wanted to mount it below the bridgedeck where it replaced an old bronze navy style pump, as that left a big hole there. I can reach it from the cabin or cockpit and I use the pump every time I board the boat(my electric pumps float switch is located high in the bilge).

It's been working great, no clogs, fast prime, no problems. I thru bolted mine on a board and then lagged the board to a bulkhead with easy access 1/2" heads in case it has to come out fast to clear something. There's a lift out bronze plate that covers the pump, not in use.