FINDING A SHORT (when your main fuse constantly blows) credit to OldSchool-IsCool and Frostyboy
OldSchool_IsCool
"To keep from blowing your paycheck on fuses, put a 12v light bulb across the fuse holder. While the light glows brightly, the short is active.
Now, start wiggling wire and unplugging connectors. When the bulb goes dim or out, you are getting closer to your short."
Frostyboy
"It may be easier for you if you don't have to replace the fuse every time it pops.
Remove the fuse and hook up at least a 21w bulb across the fuse holder, even a head light bulb if you like. If a short is present the light will glow. Move the wiring, turn the bars until the light goes out, that might narrow the search field for you."