INST Fuse blowing

Place a test lamp across the fuse socket that keeps blowing. When the short occurs the lamp glows BRIGHT, when normal current flows the lamp is dim, or no glow at all.
While you are looking at the test lamp gently wiggle harnesses and wires, dimmer, etc and try to get the lamp to glow bright.
Not only saves fuses, but is gentle on your harness and circuits while you troubleshoot.