Ok so I saw this web page which basically TELLS you how to build it, what material you need, and I decided "why not". Here's the link to that page for those who are curious:
http://www.4crawler.com/4x4/ForSale/RockSliderZ.shtmlStep 1: design it, measure it, buy the material

How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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Step 2: start the cutting and welding!

How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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How-To build your own Rock Sliders!
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