all the positives will go to fuse panel. The hot wire will come from battery to fuse panel. All the negatives will need to be joined together at the negative post of battery.
Where is the wire that feeds instrument panel fuse
It is the radio ignition fuse. Used on the power signal wire for the radio.
That varies by the installer. Some might wire it into an unused slot in the fuse panel, or they might piggyback it off an existing one (which, personally, I do not recommend). My vehicle isn't a police vehicle, but I have additional lighting on it, and I bought a Blue Sea fuse panel, and basically installed an additional fuse panel.
More than likely has 2 fuses. One in the fuse panel and another inline fuse somewhere between the fuse panel and the radio on the red power wire.
It comes from the hot wire harness from the battery through the fuse panel. It will have a fuse in the main fuse block.
red
The fuse box is constructed of a rigid plastic. Each individual fuse fits into its own slot. On the bottom side of the fuse slot there are provisions to hold a brass, aluminum, or gold pin. These pins get crimped or soldered onto the end of a wire, are inserted into the fuse panel, and are held in place by various types of "strain relief" usually clamping onto the wire insulation somewhere so no force is placed on the copper wire itself. The fuse fits into this pin tightly to make connection and supply voltage to a circuit. The main power wire to the fuse panel is usually a larger wire - 4-10 gauge and has an eyelet on the end. The eyelet fits over a threaded stud on the side of the fuse panel and supplies voltage to one pin of each fuse or relay.
If the plastic box has a ground wire attached to the GFCI and the ground at the fuse panel, you do not need to ground the box itself. As long as the ground wire is connected to the GFCI and the fuse panel, the box will be effectively grounded. Just ensure that all connections are secure and properly fastened.
Check the fuse in the fuse panel. There should be a fuse for the radio, or you have a llose wire.
trace back the + wire from the alternator to the fuse panel in front of the battery
There should be a fuse in the fuse panel that controls the power outlet. Check the fuse first, then look for a loose wire connection.
the inline fuse for the ignition requires remove the bezel panel and the gauge panel from dash. trace the red wire up and to the top rear right of the dash you'll find a lump in the wire.