Three on tree levers are on engine side of firewall, not under dash. Fuses usually blow when additional equipment has been added without consideration for extra current draw. Have at it, but I've owned the Cobra Jet for 46 years & it has virtually same fuse box as my Comet. Don't remember having a fuse failure. The headlights, exterior lights and windshield wipers have circuit breakers. Meaning the bare essentials for vehicle operation don't have fuses anyway.
I tried to take a picture of how ridiculously hard it is to get too and I couldn't even get my camera up in there LOL
I know exactly where it is. Some years back I had the complete dash harness out of my Cobra Jet and in '14 the underhood harness out of the Comet. Fuse box is part of dash harness, bolts to and has connections for under hood harness. Last time I saw one in Comet was almost two years ago, that was when I replaced the brake light switch.
XP-67 XP-67 Ford Powered EXPRESS Wiring System COMPLETE WIRING SYSTEM: 16 Fuse = 18-20 Circuits Our newest custom wiring system is built specifically for your vehicle with all the connectors and wiring necessary to drive it, pass inspection, and be able to add accessories as you see fit, now and in the future. We have included the cooling fan relay due to the fact that more and more customers are using electric fans. Now you can have everything centrally located for a cleaner installation! We've also added a Multi-Connection Battery Junction Block to reduce the number of wires going to the starter for all those add-ons in your custom Ford powered application. Panel measures: 4-3/4" W x 7-1/2" L x 3-3/8" H
I installed an American Auto Wire kit similar to that one and will not do one like it again. I did not care for the screw termination at the fuse block, I would rather have one that is terminated like the factory blocks. I bought a universal kit from Speedway for mine, great price and a quality kit. https://www.speedwaymotors.com/Speedway-Universal-22-Circuit-Wiring-Harness,229874.html
I haven't replaced the factory fuse box, but have added some aux systems. The plate will be hinged on the firewall and fastened to the dash with zeus fasteners, will swing down for access and mount where the heater box used to be (street/strip car). Wiring not complete yet, harnesses will be secured once the wiring is complete and the plate is powder coated.