Back to our 1940 Buick.
The original 40 Buick turn signal switch was old with tattered wiring. Lucky for us; the shop manual I got had a nice simple breakdown of the unit to assist in disassembly and reassembly; and operation of the unit in neutral and both directions.
So, the next thing to do is take it apart and replace the old wiring to make it new again.
Lots of small parts, so as you take the unit apart, put each part on your workbench in a careful spot so you don't loose anything. Try finding replacement parts for this thing.
After the switch is apart, take the switch in your hand and inspect it to better yourself while you take it apart. This simple slide switch is used to direct the electrical current to its perspective directional lamp on the rear and front fenders. Lucky for us, the wires are screwed on for an easy removal and replacement. Most switches have the wiring soldered in place. This should be easy.
After the wires have been removed; (Oh, be careful of the small screws...I dropped one and spent a half hour trying to find it. ) get your new wiring, crimp on the correct hoop connector, solder and heat shrink. The Heat shrink will keep the wires from any possible shorts.
After the wiring loop terminals have been installed and connected to the switch, re-install back into the housing and reassemble the whole unit.
I took my time, it took about 2 hours from disassembly to reassembly.
Remember, please take your time when repairing these switches or any others. These old units are hard to find. Make them new for another 68 years of use.