AS stated, Remove the vent and disconnect the vent hose so you can get access. Use an electricians probe;( several lengths of fiberglass that screw together). An old fishing pole without the guides may be long enough. Pull through some heavy monofilament from front to back. Tie wires to the string and pull it to the dash. There should be an access hole in the side of the boat under the dash. Go slow and use two people to lessen hang ups.good luckjwt