I will put in my 2 cents worth.I know it is hard to believe but I had the same basic problem a couple of years ago with the gauges. I had to replace ALL the gauges except the tach/hr meter and 1 speedo. They were all bad. I have never had the starting issue you are having. Make sure the inline fuse located next to the big disconnect (in the small red wire) switch is free of corrosion and seated properly.