You either have a serious short somewhere, or the voltage regulator (the one for the alternator, not the gauges) stuck and produced very high output voltage to the system.
Smoke and these kind of symptoms is usually bad. Often this indicates a harness that has gotten hot enough to melt insulation and weld wires together in the harness. The only way to find it is to untape the harnesses and inspect 'em.
You could try some of the following:
Buy yourself a "short finder"
I don't recommend this one, it's just an example
[ame="http://www.amazon.com/Tool-Aid-SGT25100-Short-Finder/dp/B002XMUGZC"]Amazon.com: Tool Aid (SGT25100) Short Finder: Home Improvement[/ame]
While doing this, keep your eyes and nose open for smoke and further damage
First, disconnect your oil and temp sender wires, turn the key to run, and see if the gauges have stopped acting up. This will at least protect the gauges while testing.
Second, determine if the problem exists with engine OFF. Turn the key to "run" look at the ammeter and see if it deflects more that expected --which would indicate a heavy drain.
If none is indicated, pull the field wire(s) off at the alternator so it will not charge. Start the car and see if things seem normal. If so, hook the alternator up, SLOWLY bring up RPM, looking for abnormal charging
Other things to try, if you get heavy discharge with the engine off, is to remove fuses and see if you can isolate it there. If you get all the fuses out and still have a problem, it's very likely a melted harness problem
Time for the "short finder" You can disconnect the battery ground, and hook the short finder from the battery to ground. A short will cause the finder to cycle on/ off similar to a turn signal. The "meter" is used to follow along harnesses, and when the meter deflects "maximum" you have found the area of the short.
Don't be afraid to dig right into this. You probably should drop the column if necessary, and pull out the cluster so you can get into the dash harness easier.
Post back, we'll be glad to help
