no dash lights at all

Should be one fuse that doesn't have power on either end of it until headlight switch is pulled to first/park lamp step. If the dimmer rheostat is good a test lamp will brighten and dim at this fuse as switch knob is turned. This is illumination but they didn't label it ill on the fuse box. Inst is instrumentation. That's their lighting, not the instrument/gauge power. It gets is supply from a tan wire from headlight switch to fuse box. The orange wire appears/begins in the fuse box, one end of this fuse.