Out of the blue the left turn indicator won’t cancel, so I pulled the fuse and made my way home illegally. Don’t tell anyone.
I disassembled the assembly and here’s what I found.
After removing the stalk subassembly, inside the case I found what was left of a small black plastic pin stuck inside the white slider that makes and disconnects the circuit when the slider is moved mechanically by the stalk subassembly.
I removed the piece and located its original position on the stalk subassembly.
I drilled a 1/16th inch pilot hole,
and then straightened a 1/16th inch eyelet and cut it to the approximate length of the plastic pin and screwed it into the pilot hole.
UPDATE 4/17/19: This fix finally failed so I replaced the assembly with a new one from Rock Auto Parts and feel like I’m driving new vehicle.