I’m in the process of a wiring my ‘52 and run across a small issue with making sure all of my circuits are protected. I started to wire the factory headlight switch and realized under that current plan, the tail light/parking lights were not protected as individual circuits. I was going under the assumption that the fuse for the headlights would protect the circuits then realized if either circuit shorts, it would take out my headlights. Then I noticed the even under the factory wiring, the parking lights are only protected by the bi-metallic strip in the original switch. Only the tail lights are protected by the fuse block on the firewall.

The new Speedway 12 circuit fuse box I bought does not have the proper circuits to route thru the block to pick up a fuse, so that is not an option. That attached proposed Electrical Diagram shows how the block is wired.

My first thought (and shown in the diagram) is to attach the parking lights and tail lights to the headlight switch, then utilize the factory fuse block for both circuits, one for the tail lights and the brake fuse for the parking lights (using a lower amperage fuses than the headlight circuit). I didn’t really want to go that route so I could keep the fuses all in one place)

I previously installed two Bosch relays (power from starter, protected by a 40 amp fuse) for my headlights, which I intend to keep so the headlight circuit does not need a high amp fuse (yet to be determined).

Maybe the Stovebolt collective has a better way!
Attachments
IMG_1122.jpeg (258.77 KB, 71 downloads)
Project Electrical Diagram

Last edited by Phak1; 02/24/2026 2:36 PM. Reason: Typo

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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