Last week I swapped out my voltmeter and fuel gauge on my 192 tournament. No issues there. This weekend I replaced the old omc tachometer with a new faria instruments tach. I followed the same procedure. Disconnected the battery, swapped out the gauge with ground going to ground, signal wire to signal, lights wire to light post and ignition wires to the 12v or battery post on gauge. Reconnected the battery and everything is dead. No power to anything. All gauges, etc... Are dead and nothing happens when I turn the key. I connected the battery correctly and also checked the battery fuse. It looks fine. The last time I had the key on was last week. Could the battery be dead and i just didnt pick up on that prior to starting the work? I hooked up jumper cables to the battery while it was disconnected and got a huge spark. I figure the battery is fine, but my jumper cable test is probably not the way to check a battery. What in the heck have I done? Any help would be greatly appreciated. Thanks! 