there was no fuse panel standard on the TF trucks, they only got one if there was accessory electrical stuff ordered [radio, etc - it was on the inside firewall just above the clutch, looks
like this] - the light switch has one fuse on it for the light circuit, and also has a pair of heat sensitive bi-metal type "circuit breakers" for the headlights alone .... could also be the switch itself, the dimmer switch, or wiring
Bill