tach problems Starcraft SFM with 90 Merc

[todd]

I have a new starcraft with the "next generation" gauge cluster, similar to cars. The gas, tach and fuel are all in one sealed unit. Anyway, when I first purchased the boat last summer, rpms at WOT were right on the mark at 5400. A few weeks later, I looked at my gauge and while running at WOT the needle was pegged. I took it back to the dealer they said it was fixed but it wasn't. I checked the dip switch settings myself and they are set according to the sticker on the back of the unit. I don't think the motor is actually overreving. It sounds the same and has never overheated. Has anyone else experienced similar problems. Would it be easy to hook up another gauge?

Thanks