Dash lights do not work.

No dash lights? no warning lights? Then ignition is not being turned to ON. Check all your fuses. Recheck your replacement work. Battery cables clean and tight? Headlights work? If lights are bright, battery is good and cables are good, so key to ON should light up warning lights on dash. If not something up still with your ignition switch.

The dash and tail lights are on two different circuits, and the brake and turn signals are on different circuits, so at least 4 circuits total.
I would start at the headlight switch and check for power on the first two issues.

check battery, also alternator

Check the tail light bulbs, check to make sure the dash lighting switch is turned up but not turned so far up that the interior lights come on when the door is closed.

Is the dash light dimmer control turned to "OFF"?

My dash light doesn't work either, I lose lights in dash at night when I have the headlights on. As for your car, thats kinda weird your fronts work but not the back. Have you already checked the fuse boxes? they are on the driver and passenger sides almost under the dash in front of the doors. If all your fuse are good and in the right spots, then I would check the bulbs out back to make sure they are not rusted inside or cut or something like that.

yes ,
check the fuses.

No. Dash lights being out could be a bad headlight switch, since the dash lights are routed through the headlight switch, not the dimmer switch. Park and tail lights also controlled by the headlight switch.

The running lights and dash lights are on the same circuit.The brake lights and turn signals are on their own circuit.You need to use a 12v test light to see where the circuit is broken,starting at the fuse,then the headlight switch,then the dash harness.(If the headlights work,you at least know the headlight switch is getting power).

I just had the same issues. No headlights, interior lights, power door locks, radio controls on steering wheel, or dash lights. Pulled every fuse in cab and under hood, not a one was bad. I disconnected the battery terminals for a few minutes. When I reconnected them every thing was working.