I've read related threads, but nothing seems to match what I’m experiencing. My dash lights for the volt meter and pressure gauge light up find. The tach and speedometer do not get illuminated. I swapped the volt meter and speedometer bulbs and the situation remains consistent. So it's not the bulb, right? This leads me to a second concern. How many bulbs are there? When I swapped the bulbs I thought there would be only one bulb per gauge. As I later read reatedr threads, I noticed someone mention 4 bulbs for the tach and speedometer each. If this is true, are the bulbs in series. Meaning, if one bulb is bad, then the whole gauge doesn’t light up. Any advice or direction would be appreciated. Thanks.