#5 (5A) keeps blowing

Here are the OEM wires for that truck. If the wiring pioneer has up is correct, you should have a yellow wire that is for constant battery power, that should go to the pink wire on the trucks side. Next would be a red wire for switched power, which should have a red wire with white stripe on the truck side. Now they show an orange wire with a white stripe on the radio side for the lighting in the radio, that one should connect to a black wire with a yellow stripe on the trucks side. That one should tell the radio that you turned on the lights and it should dim the radio lights. That is adjustable in the radio's controls. The last wire on the radio to be concerned with is the black ground wire, it connects to either a solid black on the truck side. The orange wire (which is the light dimmer) coming from the truck side of the harness doesn't get connected in this application. We will assume the speakers are correct if you hear sound.
If you had a solid orange on the truck side connected to a solid black that was likely the issue as the only solid orange is the lamp dimmer. I would double check the wiring and put the fuse in and see what it does. Hopefully it brings the OEM dash lights up.

Leave the orange wire disconnected and see what the lights do. No rush.

The solid orange shouldn't be connected at all. Someone put it into that connector without testing what it does. Currently it is connected to a ground. So that connection is a short.
The capped black wire with yellow should have power when the headlights are on.
Disconnect the orange and connect a test light between it and the ground. Now plug in the fuse and turn on the marker lights and move the dimmer, the light should get brighter in response to the dimmer.
You don't need the black with yellow connected if you don't want to bother, it just means the radio's lights stay on full bright regardless of the marker or headlights.