I make an aluminum bracket to mount it but if you want to do it yourself I would got to the hardware store and buy two steel right angle brackets Like shelf supports 3/4 inches wide by 5" by 5" with holes in them and with a hack saw cut both of them off on one end and leave about an inch and a half. The 1 1/2" part will support and extend over the edge and the 5" part will attach to the alpine mounting brackets. (you will have to do some drilling to both mount the alpine brackets to the rt angle brackets and mount the rt angle brackets to the horizontal edge next to the spare tire. I hope you can understand this procedure.

Scott@Lajollaaudio

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The Mercedes Specialists Since 1986