Does anyone have a digital tach in their boat? I saw one for sale in a Eddie Marine catalog. It says it's accurate to within 1 (one) RPM. The current tach in my boat has started reading about 1000 RPM high, above what used to be 3000 RPM. At WOT the tach pegs at 6000 and I know my motor isn't turning anywhere close to that. I have a Comp 9000 distributor and a MSD box. Are digital tachs hooked up the same as regular tachs? Has anyone else ever had a tach start to missread similar to mine?