Quite awhile back, I replaced the stock alternator with a 130A version. It's always been ok until just recently, the gauge is almost out of the normal range on the high end. Is this a gauge malfunction or and I going to fry something?

 

Check the votage coming out of the alt. The reg. may have gone haywire, and it could be trying to charge wide open, and thats no good. It should be charging about 14 volts to 15v. is max.

 

You could fry something if your gauge is working correctly. I would take a meter and check the output of the alternator. If that is high then I would check the voltage regulator. If it is OK then I would be looking at the gauge.