we mounted the switch and pump on a heavy plastic base which fit snugly into the bilge bottom (a piece of fiberglass works well too). By laying prostate on the sole we could just reach it for removal, cleaning, etc. Should the sump be deeper than you can reach, a pad-eye or u-bolt can be installed on the base that can be hooked with a short stick with a hook on it. I have also seen some bolt an upright stick/handle to the base for easy removal as well.

By the way, I like the Water Witch, solid state, activating switch, it's not much more money than a mechanical switch and in my experience works better and longer, without possibility of jamming from trash etc - the Coast Guard uses them in their boats too (no, I don't own the company - wish I did though ).