Problem with electrical

Hi, I have a strange problem. When I turn on the lights on my '80 all the engine gauges stop working. They light up, they just wont work, all needles fall back to off positions. I turn off the lights; everything works fine. Any ideas where I might start?
Thanks in advance,

Pete

Sounds like it might be a problem with your guage circuit cluster on the rear of them. Just a thought, I never heard of this.

I think that it is a ground problem. Not to good at this but when you turn on the lights they are searching for ground going thru the gauges for ground. Try to get a good ground for the lights. This is a stab in the dark like I said not to good on electrical. Chuck