Dimming lights...bright lights...dimming...bright...

I have to ask because I think I have an overload in my head. I have a similar problem. I have a ground from my alternator to the body, I have a ground from the battery (neg) to the eng block and I put a new ground strap from the battery (neg) to the body. I added another ground from my valve covers to the body.

My lights go dim and bright when the car comes to an idle. Also my inside gauges do the same.

I was told to add the extra grounds from the battery to the frame and from the valve cover (passenger side) to the body, so I did, still the same. I have a powermaster alternator and a red top battery.

I also have to use my high beams when driving cause my lights seem so dim.

One other problem that I seem to always have is with my Tach. I have checked my connections which all seem fine however it will work just fine for a few days and then like the other night it will just stop and then start again. At idle it the needle will go all the way down, however upon acceleration it will go back up again. Sometimes bouncing around, up and down and then again at idel, just stop. This is driving me nuts.

Whew,,,,,,,,,,that was a mouthful. lol Suggestions????