Whether you're in need of a replacement electrical fuse system for an old vehicle or you're needing to wire a vehicle from scratch, there's a way to put together a reliable fuse block on a budget. If you're dealing with a rig that's decades old, chances are it uses a glass fuse block and the connections have aged and corroded over the years. Modern vehicles use plastic push-in fuses that are more reliable and easier to service.
There are aftermarket fuse panel kits that include multiple fuses, relays, and wiring bundles. However, while easy to use, they can be fairly costly. If you have some time on your hands and/or want to create your own fuse panel you can start with a factory one from a salvage yard vehicle. There's a wide variety out there, they're readily available and are quite cheap.
You can get simpler ones or very large ones with many fuses, circuit breakers, and relays. You'll get one or more power input feeds and then multiple fused output wires in an array of colors. If you go with the original intended fuse sizes, the output wiring will already be sized to match the current capacity of the fuse. If needed, wires can be moved around or replaced by swapping connectors on the fuse panel or its connector.
Granted, there is some price to be paid. You will have to decipher the fuse block electrical routing and figure out how you want to wire it into your vehicle. We've found there are typically convenient ganged fuses that are supplied from a single input (such as 12-volt battery or ignition) and some stand-alone fuses that can be powered from other sources as needed.
Depending on how complex your vehicle electrical wiring is can determine how big of a fuse panel you might seek. It's best to get one larger than needed, as you're likely to find fuse circuits that are wired internally to the block and difficult to use, or ones that don't have the electrical configuration you want. There may also be larger, high-current fuses or circuit breakers that could come in handy as well.
This 2000s vintage GM truck/SUV fuse panel (backside shown) has a large plug-in connector on the back that is part of the vehicle harness. You'll want this connector and possibly others that mate to the fuse block, along with harness wiring. You can find fuse blocks both under the hood and in the interior of vehicles, and some will also serve as power distribution panels with useful power connection points inside.
Some panels will come equipped with relays and may be reused for your application. These relays from the GM panel are rated at 20 amps (small) and 35 amps (large). There was also a flasher module on the back of the panel. We'll be using it as well in an application. As mentioned, it will take some detective work with an ohmmeter to trace down some of the circuits, and a wiring diagram may be useful during the process.
Along with pulling a fuse panel, there are lots of other useful electrical components that can be pulled from a salvage vehicle. You have access to plenty of high-quality wire in multiple colors, including high-temperature–rated wire in the engine compartment. Assuming the vehicle is not many decades old and the wiring lies inside a protective sheath, it should be in fine condition. There are also useful battery feed wires, ground distribution wires, and power junction blocks that can be useful.
Along with the fuse panel, you can often get its mating bracket for reuse. In this case, a bracket was mounted near the firewall of this 50-year-old vehicle. The modern fuse panel slips in place, secured with barbed clips.