It seems when ever damp weather comes on, my ignition becomes a bear to start (once up and running everything's just fine).

There's 6.25 volts at the battery but at times only 4.24 volts at the coil!

After thoroughly testing the ignition circuit, I think I traced it back to "dirty" ignition switch.

Before I yank it out I'd appreciate some ideas on dismantling and cleaning these switches.