[RustyPile]

There is no fuse for the headlights. Headlights are protected by a built-in circuit breaker in the switch. The red power feed wire for the headlights is protected by a fusible link. You'll need to reference a wiring diagram for the following tests.

Using a test light or voltmeter, check for 12 volts on that red wire at the headlight switch..
If no voltage, check for a blown fusible link or broken wire on the main power distribution circuit. If you have voltage, turn on the headlight switch and check for voltage on the light blue wire. If no voltage, the headlight switch is bad..

If you have voltage, check on the light blue wire at the dimmer switch. If no voltage, there is an open in that wire between the dimmer switch and headlight switch. If you have voltage, check for voltage on the light green wire and tan wire at the dimmer switch. Voltage will alternate between these wires as you flip the dimmer switch.. If no voltage on either or doesn't alternate between the two, the dimmer switch is bad. If voltage is present on both, check for blown headlight bulbs or bad connections.

As for no backup lights. Check the fuse first. If it's good, with transmission in reverse, check for voltage at the backup light bulb sockets. The light green wire carries current for them. If voltage is present, check for burned out bulbs. If no voltage, Start moving forward with checking for voltage.. Many things can cause this problem. Loose or corroded connections, broken wires, bad or misadjusted backup light switch..

When an electrical gremlin rears its ugly head, it's next to impossible to point directly to the problem.. It goes unstated, you MUST have satisfactorily operating grounds....