Sure, I can sketch one out. Take a brass or steel lever, crank it, couple it to a needle on a calibrated dial, and have a light‑sensitive cell—like a photoresistor—attached to a pivot that the needle moves over. Add a simple mirror on the shutter assembly so the cell only sees the scene, not the ambient light inside the body. Tie the gear ratio to the f‑stop range, so turning the dial directly sets the exposure value. No chips, no firmware, just a little mechanical brain and a bit of soldering.

Right, use only a few bits: a brass gear train, a needle on a 0‑12 stop scale, a photoresistor in a tiny light‑tight housing, and a 45‑degree mirror on the shutter rail. Run the gear from a small handle, check the needle against a calibrated reference on the darkroom bench, and tweak the pivot until the needle lines up with the correct exposure. Keep the assembly in a sturdy metal bracket so it won’t wobble, then you’ve got a hand‑operated meter that feels like a piece of the old SLR itself.

Glad you approve. Just tighten every screw, run a few test exposures on a print plate, and you’ll have a meter that feels like a relic, not a gadget. Happy tinkering.