Before you mount the pump, you might want to fill the boat with water and see where it puddles as the volume goes down. I think these work better on a boat with front and rear bulkheads that restrict the water to a small area. Because my Mariner XL had no bulkheads I added one as a safety factor. It was placed, centered on the keel, behind the fixed seat. It was “okay”; not wonderful.
First, I didn’t realize how nice it was not to have anything in the way when loading bags in the stern. Though the pump was not large, it always made itself known as I was loading or retriving gear.
Second, The Mariner, with fixed seat, had about an inch of foam under the seat and up the sides. That allowed a small, but definite, amount of water in the front from reaching the pump behind the seat.
Third, The way the interior space was designed, the water wouldn’t pool to one place unless the boat was rocked on its side. But the pump was mounted right on the keel (center). So it couldn’t reach the “nuiscience” water that remained after the majority was pumped out.
If there were a rear bulkehead - with extra points if it were slanted, so all the water pooled behind the seat and the pump was located behind the seat and in front of that bulkhead - that might work. Or maybe it would be more out of the way if it were along the keel near the bow bulkhead. Problem with that is, if you ever needed to work on it, clean out some pebbles, etc. it would be difficult to service up there.
I only used it once, purposely flooding the XL at Pirates Cove. The pump worked like a champ, removing most - but definitely not all - the water. I sure wouldn’t have wanted to do that with a manual pump. But if I were paddling with a friend, we’d probably drain the boat on his/her deck.
If I had dumped paddling solo, with a loaded boat (no leverage to lift it in the water), I would have been REAL HAPPY not to have to pump out the water by hand - especially if conditions were lumpy enough to dump me.
I never had a problem with the magnetic switch but I did put some protective clear film under the slide path (It slide on a deck bungee cord from one side of the deck [off] to the other side of the deck [on].