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Rock-Light Installation

You saw it in the magazines, and you thought, "Sweet! This guy has a light bolted to the frame of his rig so he can see the terrain under his vehicle at night! I have to do that!" ... Well, I'll admit, thats how it happened with me. Its a really easy and inexpensive modification you can perform on your vehicle to make night-wheelin' a much more pleasurable experience. It doesn't matter if you are stock, or if you are a big-dog rock-tractor driving gear-head. You'll be surprised to find a frame-mounted source of illumination quite an asset on the trail. When I pick lines on a trail, I initially look over the hood in front of my rig and say to myself, "Alright, I'm going to put the driver-side on those rocks over there, and then I'm going to get my passenger side on these rocks... straddling the gap..." and so on, and then a quick glance at the ground below me usually tells me if I'm on track with my original line or not. As you well know, its pretty hard to stick to a line when you or your spotter can't see the ground under your vehicle! This is where the simple "rock-light" comes in handy.

Okay, here's my disclaimer. I'm not an electrician, but a humble four-wheeler passing along some helpful "how-tos" the best way I know how. I learned the ins-and-outs of setting up vehicle lighting by wiring many sets of Hella's... by no means the easiest aftermarket off-road lights to install, but an invaluable learning experience for the non-electrician. I used this new-found knowledge to my advantage with the whole "rock light" concept. If you are an experienced automotive electrician, and see something in the following pages that is incorrect, or a fire-hazard, please feel free to let me know so we can make the proper amendments to my rig and the following write-up. :)

So you survived the disclaimer and would like to install a rock-light of your own. Not a problem... the following pages show and describe how I installed a rock-light under my 1999 Jeep TJ. The installation procedure is not specific to any particular kind of vehicle. The only thing that is vehicle specific is the rock-light mounting location, and that is entirely up to you. Lets begin with the things you need!

Rock Light You need a rock-light itself. In actuality, the "rock-light" is a sealed beam tractor-light encased in rubber, and is stud-mounted on a swivel base. One wire comes out of the rock-light, and the metal base is your grounding point. Rock-lights can be purchased at a farm store, a Napa, or most auto parts stores for between $10.00 and $20.00. We recommend you ask the clerk for a "tractor light". Their inexpensiveness, and tough nature makes them the perfect frame-mounted light fixture.
Rock Light Other items you may need include electric tape, an inline fuse holder that I picked up at Radio Shack, 20-amp fuses, many miscellaneous wire connectors, zipties (which are priceless), and a relay. You'll also need a switch to turn your light on and off from your dash, and a way to fasten the switch. In my particular case, I needed extra-strength double-sided adhesive.
Rock Light Thats not all! You're also gonna need plenty of wire. I've got a large spool of "12-Volt Primary Wire", 14 gauge. How much you need depends on your vehicle's configuration. You'll need a wire cutting/stripping/crimping tool and miscellaneous common hand tools. For instance, a wrench to detach your negative battery terminal prior to the installation.

Finding a spot for your light and running the initial wires...

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