If you could back up your van before with out hitting anything you probably wont need the back-up sensor.
Good luck in your search. Did you try
AutoTrader.com - Buy Used Cars, New Cars, Sell a Car, Find Car Dealers that is where I found the deal on my Vette I just bought and my 1998 Windstar ?
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Mark V
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1998 Explorer 4.0 SOHC
1998 Windstar GL 3.8
2001 Corvette Coupe 6 Speed
2006 Honda Shadow Spirit 750
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