This turned out to be pretty simple. Yes, work from the back, loosening the clamp that holds the clam-shell-like cover to the throttle stop cable. Then remove the 6 screws on the clam-shell itself and slid it downward so you can get at the backs of the switches. Now go around the front and remove the rubber switch cover, retained by a large hex nut. You can now push the switch inward so you can remove the back of it from the panel. What I found was revealing and perhaps a warning. The reason the switch had such a long throw and spongy feel was that the back of it, either pressed or glued at the factory, had simply separated from the front housing and was being held on only by the pressure of the two cables being connected! When I removed the two wires, I had two sub assemblies, a spring and a couple of metal contact wafers in my hands! How long could I have gone with things in that state? Who knows, but I know it would have quit exactly when I did not want it to right? Moral is to be sensitive to subtle changes as your boat will in fact communicate things to you.....