Turn signal issue

I have a 1971 M35a2. I had the truck out for a parade on Memorial day, everything was fine. I pulled it out of the garage 2 days later, I have no left turn signal or 4-ways. Right turn signal works just fine. When I put the left or 4-ways on, I get a hot wire on the back of the main light switch.

I checked all grounds, no corrosion. checked the grounds on the bulb sockets with a continuity tester--all the way to the ground on the battery. All were good.

Does anyone have a full out wire diagram for the truck with the wire numbers marked? And any other suggestions would be great!

Thank you in advance for all help.

I can't see this very good. I hope you got better eyes.View attachment wiring diagram Model (1).pdf

https://www.steelsoldiers.com/showthread.php?3843-Peter-Bog-s-CAD-deuce-schematic!

https://www.steelsoldiers.com/album.php?albumid=4737&attachmentid=764143

The flasher units are known to go bad. Cheapest bidder. Still $$ to replace each time.
There is a thread on how to build your own with a 24V flasher relay. Did that, never looked back.

The turn signal switch is easy to open up and clean . I have cleaned several to solve various symptoms. A small piece of sandpaper on the contact surfaces and a little lithium grease goes a long way. It is a good place to start your troubleshooting efforts.