Yes, I gave you the link in my post. The link covers how to. Actually600 emery paper to clean it?
Use any section of the switch that creates the ON-OFF function?Okay I have
bottom two ports - no continuity when off so I feel confident the hot wire will go in one port—but which one?
Top half- both ports always continuity
If you are using 110V to power a 2.5HP motor then the current will be about 17A nominal. Your new 12A rated switch appears inadequate, unfortunately. Even the original switch should have had a higher rating.I was given, what appears to be, a pretty good used replacement (however amps rating is 12 vs original 16.)