Our '86 H31 has Datamarine depth gauge and knot meter. The knot meter works pretty well most of the time, but the depth gauge has been iffy for the past couple of years, and this year especially it doesn't seem to be working much at all. Rather than try to get it repaired (I know Datamarine is out of business, so that might be a big problem) we're looking to replace the instruments. They're also almost 20 years old. We'd appreciate any recommendations that anyone has for what a good, reliable, simple (if there is such a thing on a boat) replacement might be.