Gauge problems again

I have all of the correct wires hooked up to the gauges and the speedo cable hooked up, but it seems like none of the gauges are working right. When I start the car, the FUEL, OIL, and TEMP needles all move to the right side right away. Then as I i start driving her, they gradually move back to left. I can't tell if they are reading correctly or not, because it seems like they work for about 3 minutes and next thing I know, all of the needles are pointed back to the left. I don't care that the AMPS aren't right but it'd be nice to know if i'm out of gas, overheating, or high/low oil pressure. The speedo works though (I thought it'd be off since I just put on 17" wheels) Anyone have any suggestions to why the gauges are acting funny. I know all of the wires are hooked up correctly. Where are the oil and temp gauge wires connected to on the engine?? Thanks.

Thanks guys. I'll try what you suggested.

Well I finally got around to finding out the problem and I'm pretty sure its the instrument voltage regulator. One of the two connections on the back of it is really loose and when I play with it the needles either stop moving or keep going to the right. When I checked the voltage with the ignition switch in the ON pos. it jumps around like crazy, from 0 to 11 to 8 to 3 to 0 to 11 etc. Correct me if i'm wrong but i'm pretty sure it's the IVR.

The voltage regulator is just hanging there. I have a feeling it should it be attached to something??? Why are they so expensive? I found one on californiamustang.com and it was $30.

So now I think I fried the voltage reg. Gauges don't even work now. I'll just buy a new one on Monday. Do the dash lights happen to run through that regulator?? They don't work now when I turn the headlights on, they only work when I turn the light switch all the way to the left so the acessory lights are on.