Turn signal wiring on F59 w/Utilimaster

School me please, on turn signals:

I've seen this fuse block in other Ford vehicles:

I'm struggling as to how the turn signals are wired. The rear lights work, but the lights in the flip-up hood no longer do.

(Bottom line - I might just run wires from the back lights to the front lights and be done with it, but that's not ideal - or a "fix" - it's a work around. I'd really like to know why the current connections don't work)

The flasher has two blades, 90° from each other, one with " Hot When 'On' ", the other cold. When the turn signal switch is 'on', the _other_ blade now has a "high-low" voltage (like 12.3V-2.3V, repeating).

The "Hot When On" blade has jumpers to 2 other fuse positions.

Is there an output from the flasher that goes to something else that returns to the stalk switch to determine which signal to light?

Is the stalk switch a ground connection switch that completes the circuit to light the indicated turn signal?

I'm baffled by what's underneath the dash.

Background:
A mechanic did some electrical work, but likely didn't touch this issue or cause it.

None of the exterior lights were working when I dropped it off at their shop for repair; I just knew I couldn't get it started. Turns out that was the glow plug controller.

I got a new headlight switch and a new knob online, and a nut (previous post) to hold it in the dash.

The headlight switch doesn't work the running lights with the wires in the original connector, though the connector fits in the new switch.