I have done a lot of electrical work in this truck. Some of it was to make it more reliable and some of it was to add new functionality. One thing I have wanted to do was to wire up my seat heaters, GMRS radio, and a fuse box to run some aux gear. I have gone back and forth on how to do that as there are lots of options (switch based, auto on with the ignition, etc). I finally decided to have ignition power trigger a high amp relay to send power to a fuse box where I can then have 6 different fused circuits. The relay I am using is an 80 amp relay which will power a fuse box where I will have the two seat heaters (7.5 amp each), the GMRS radio (15 amp), 12v power out for a portable fridge or other gear (30 amp), USB charging (5 amp), with one circuit open and 15 amps to spare.
By making the fuse box auto triggered from the ignition and moving the GMRS radio power to the fuse box I can free up two switch bays in the center dash. This means my 6 switch panel in the center dash will now have 1) air compressor 2) front locker (future install) 3) rear locker (future install) 4) winch power 5) open and 6) open. I wanted a clean look and to make the GMRS radio secure (hidden) so I installed it in my locking cubby box. The unit is a Midland MXT575, 50 watt, GMRS, with the display built into the mic so you can hide the base. I also wanted some more USB charging options in the center dash so I installed 2 USB charges by the switch panel that will power my phone and Garmin GPS.
One might say all of this is a bit over-engineered but the way I look at it I have put in modern wiring, increased functionality, fused everything separate for safety, future-proofed the design by running more wires than I need, left myself some open circuits as my needs change, but kept the original look of the Defender. So ya….its over-engineered.