I recalled the several occasions while I was restoring a couple Slash 5s and did the “deep dive” into them, their perches and levers. The 1970, 1971 thumb buttons had screw & eye connections on the back of the switch; maybe when the Short Wheel Base Slash 5s got stretched to Long Wheel Base, the screw & eye connections were change to pin & socket.
Regardless, the electric contacts are really exposed to the weather, particularly as the “guts” of the switch face forward and capture everything !
Here’s a typical initial disassembly picture…
As alluded to in prior posts, corrosion has severely affected the contacts ! The spring is what gives the functional “feel” or “click” to the turn signals/high-low-flash headlight as well as, keeps the brass washer separated from the two(2) prongs in the base. Those prongs, contacting the washer, actuates the Starter Relay or Horn.
To disassemble the switch, that spring must be fully depressed, to extend the shaft out of the pocket in the backside of the base, to free the E-clip… you Star Trek fans might know this as, “the Vulcan Nerve Pinch”, by Mr. Spock, which causes intense pain and numbness of the thumb !
While tears of pain are running down your face, thumb and fingers crippled, the E-clip rockets to the Black Hole in the shop space ! Paul Glaves has it right: best to work in a dry cleaner’s transparent garment bag !
I believe the triangular male contact piece was silver plated brass originally ? The corrosive “bloom” I’ve seen, has the green-blue look of silver oxide.
I clean all the components with Safety Solvent; use ultra-fine glass bead media at low pressure, to blast the base and button; lightly apply dielectric grease and, having “steeled” myself for Mr. Spock… reassemble. Perform a functional circuit test on the bench. Accidentally, I found that a light coating of silicon dielectric paste, applied to the Bakelite button, restores the nice, subdued “charcoal’ color without shine…
I noticed a design change within the switch when they transitioned to the “pin & socket” electrical connections: the brass washer now had three(3) tangs in the inner diameter to grip the pivot shaft. Earlier, the 1972 R 60/5 shown in my banner, would automatically engage the starter even with the engine idling ! Hours of troubleshooting later, I found the early brass washer was loose from the rubber cushion below it and… was welding itself to the two(2) raised tags. When system voltage dropped and the alternator light illuminated, the Starter Relay sensed a “start” condition ! I glued the washer to the ‘rubber baby buggy bumper’ and made a note to do that to all early switches going forward.
Here’s a picture of all the components; serviced, painted, polished, re-plated with Cadmium/clear-Chromate; ready for bars…
Anything Worth Doing, Is Worth Doing To Excess 
