Wouldn't it be easier to just buy a chrome/billet backing plate like this? Only $16 and ready to drill the needed holes, right?
http://www.cruisercustomizing.com/detail...&model_id=0 
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SO....went to Lowes today and found they have a much better selection of steel plates than Home Depot.
About $10 for a 8x12 sheet...thick enough to keep it stiff and possibly mount the signals to, thin enough to look good.
Had to resort to using my jig saw to cut it all out.
