1992 sentra meter fuse blows constantly

[yumgrinder]

I need some guidance, the "meter" fuse (interior, by drivers door) on my 92 Sentra S 5 speed manual (1.6 liter) keeps blowing. It'll blow the biggest fuse I put in there (I know, not safe, I was troubleshooting). It started doing it awhile back on occasion, and I could never make it do it on my own terms. Now it does it every time it is replaced, almost immediately. Sometimes it'll hold for a few seconds though. There is nothing aftermarket in the car, besides the stereo but I have removed power to it in case maybe that was the issue. I had installed a cutoff switch and push button ignition at one point but I completely reinstalled the stock ignition to troubleshoot. My charging system goes out when the fuse blows so I can't drive it as it is. If it blows 20amp fuses, I'm afraid to put my multimeter in line as it may blow that too?

Any advice? What should I check? Since it was progressive, do you think maybe my alternator has been in decline and now it needs replaced? Would it blow fuses if it were to go bad in a weird way?