Here's a step by step pictorial of building a floor pan...enjoy 
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| Make a template out of cardboard... | 
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| Transfer dimensions to a piece of 18ga... | 
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| Cut along the lines...drill holes for the shifter clearance... | 
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| Finish cutting the shifter clearance hole | 
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| Induce some stretch so that the bead rolls do not cause the piece to go crazy... | 
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| Add some decorative beads... | 
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| Admire... | 
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| Add a slight flange around the outer perimeter | 
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| Add a slight roll the the shifter clearance for strength... | 
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| Install | 
