Self Canceling Turn Signal Problem

When I make right turns the self canceling turn signal unit correctly turns off the signal. However, when signaling left, it will stay on all day if I don't manually shut it off.

Is it most likely the self canceling unit itself or another part? I picked up an 82 unit from ebay for cheap but even though the unit itself is the same exact size with the same markings, the wires coming out of it go into a connector that doesn't fit my bike.

Any ideas?

If not already at hand, the wiring diagram may be found here

Wiring

Control unit may be okay since right signal is working.

Am guessing bad connection inside the turn signal switch (may need cleaning) or in wiring from switch to turn signal control unit.

Thanks Patton. I'll give it a go and see if that helps.