I just trailered my pontoon down to Florida from NC. Since I'm learning the channels around Hernando Beach, I bottomed on a reef, and now my trim guage is out of whack. it only shows 3/4 to all the way up. The motor is going through the full range, it only seems to be the guage. Where is the sending unit? Is it a mercury tube or a potentiameter?My manual is home in NC. Any help would be appreciated. Thanks !!