I have a 1993 Bayliner Capri. The boat did not come with a trim gauge but it came wired for it. I bought a trim gauge for it, hooked it up to the brown/white wire under dash, the ignition wire and a ground and its not working right. The gauge bounces back and forth a lot while adjusting the trim and doesn't correspond right at all to the trim position. The gauge will read all the way up when it's not etc.. Does this sound like a bad gauge or something else? Thanks!