Here is a pic of my ramps. I don't work on wood projects, but I think they came out good.
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In total I made 4 sets. Two sets per wheel. The wood planks are only 6 inches wide.
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Just line them up and drive up the ramps. It works for both front or rear.
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You can see the "slanted" cuts on the steps. It helps to drive the car up the ramps.
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When done with them, just stand them up against the wall and done deal. If you want the dimensions send me a PM.