The wiring project is officially finished as of last night. 
Let's summarize what my goals were when I started this wiring project 6 weeks ago, how that fleshed out, and specifically what harness modifications I did.
Goals:
1. Move batteries to the center of the vehicle to make more room for activities in the engine bay.
2. Battery Isolation
3. Clean up unused systems in the factory harness (original 2f emissions control systems, rear heater, etc.)
4. Clean up engine bay wiring
5. Remove hatch washer and wiper
6. Integrate 12v accessory wiring into harness (into factory fuse box if possible)
7. Increase overall battery capacity
8. Have ability to monitor battery bank charge rates
9. Move HAM radio head unit to above the rear view mirror (eventually create overhead console with lights)
10. Eliminate stereo deck and move to headless stereo system
Bonus Round:
- all harness loads are off of the lithium battery bank, including the fusible link and aux fuse block
- AGM batteries are wired in parallel, and charge through the power-gate, but power only the starter and winch
Doing this meant relocation of a few things in the harness, elimination of a whole lot of things, and adding a bunch more. I broke it out by harness location and harness contents:
Center Dash to batteries (entirely new harness):
- fusible link wires (moved from PS front engine bay harness)
- ARB compressor switch signal
- ignition + signal for power-gate charge indication
- battery join control wires
- ham radio power wires
- fan controller power
- dash 12v socket power
DS Dash to rear quarter panel
- remove defog circuits
- remove wiper circuits
- remove washer circuits
- splice hatch LED light harness to dome circuit at the top of the d-pillar
- rear fridge/socket wires
DS Dash to DS front fender:
- remove horn wiring and add back new horn + wire (will explain later)
- winch contactor/solenoid control wire bundle (power, ground, in, out wires)
- retain/repair side marker, turn signal, and headlight wiring
- starter + and - 1/0 wires through bulkhead fittings
PS Dash to PS front fender:
- fan controller power
- fan controller constant on
- fan controller constant off
- fan controller constant ign +
- alternator 1/0 + wire through bulkhead fitting
- AC clutch signal wire
- oil pressure sensor
- pyrometer thermocouple
- wiper motor
- washer motor
- remove all emissions equipment wiring
- remove charge circuit wiring (has been defunct since engine conversion)
- remove horn wiring
- retain/repair side marker, turn signal, and head light wiring
Center Dash to Engine harness (entirely new harness):
- injection pump signal wire
- starter solenoid signal wire
- reverse light switch wires
- fuel pressure sensor wire
- tiny-tach inducer sensor wire
- coolant temperature sensor wire
- line lock wires
DS Dash to Overhead harness (mostly new harness):
- OEM dome light wires
- *future* light bar power wires
- gauge backlight + wire
- ign + and - wires
In the main harness that runs through the dash, all of the redundant or unnecessary wiring was traced and cut out. This removed a substantial amount of wire. The gauge cluster wiring was audited and consolidated to reduce the number of connections, the gauge pod wiring was cleaned up, and new speaker harnesses were created and added in. All of the wire additions above were designed to be able to be disconnected for when the harness comes out of the truck, with exception of the center dash to battery harness.
OEM Circuit modifications, sorted by OEM fuse.
Two primary fuse box circuits were entirely rewired for the purposes of this project. As part of this project, I created a modified HVAC bezel to utilize carling rocker switches instead of trying to source OEM switches. I also eliminated the OEM cigarette lighter and ashtray in favor of a blue sea cig/USB combo deal. Since all of the HVAC switches were eliminated, this left the DEFOG and CIG circuits open to whatever I wanted. The rest of the circuits listed here were partially rewired, but all left with the OEM fuse rating, and matching (or larger) wire gauge, to prevent shorts.
CIG
The carling switches I got from delcity.net have a 15a rating (i think) but I'm using them for low current operations. To list the purposes, ARB compressor relay signal, power-gate battery join, line-locks, fan controller constant on/off. For this purpose, I rewired the CIG circuit to power my carling switches, and the new headless stereo amp I put in. The wire gauge was matched to the OEM power wire, and the factory rated fuse was retained in the fuse block.
DEFOG
The DEFOG is a 20a circuit that ran all the way back to the rear glass to power the rear glass inductive heating strips. Since all that was removed, I repurposed this to a different carling switch, which will eventually power a light bar that goes on the roof.
IGN positive (ENGINE)
For the handful of places I needed IGN + to signal the ignition was on, I leveraged a black-yellow wire from the ENGINE fuse circuit. This is a 18ga wire in the factory harness, which is fine because the devices wired to it use it as a voltage sense to switch on, not to carry current. The IGN positive was ran up to the fan controller to signal that to turn on, and back to the power-gate, to tell the power-gate to turn on to allow the alternator to charge the batteries.
DOME
I have a pair of LED flood lights in the hatch that I added some number of years ago. For forever, they've been ran off of 18ga wire on a 5a fuse. I eliminated that harness, and elected to splice them into the rear D-pillar DOME circuit where the rear dome light connects. The DOME circuit is 7.5a, and is perfectly suited to this. I will still have a switch in the rear hatch to manually turn on the hatch lights, so that they do not come on when the doors open.
HORNS
The horns were interesting, but after some thinking, they came out pretty slick. HAZ/HORN circuit in discussion. As those of you with 60s know, the horn button on the steering wheel switches the ground leg (solid green wire) of the horn circuits. The green/orange wire is a constant power wire (12v all the time regardless of key position). This works with the OEM horns, as the OEM horns are isolated from their mounting location, so when the ground is connected by the horn button, current can pass through the harness constant + wire, through the (now connected) ground and the horn activates. The issue is that seemingly all aftermarket horns HAVE to be + switched, as they ground through their mounting studs.
The fix for aftermarket horns is to run a relay with a power source from the battery, using the OEM circuit as the relay signal, which works well if your battery is still up front. Well, since i had the whole harness apart, and my batteries are in an inconvenient spot, that wasn't going to work well. I figured out that you can power and switch a relay all through the two OEM wires, and get a single horn button activated positive output wire to power the horns with. Green wire (switched ground) goes to one of the two relay switch pins, and the green-orange wire (constant +) goes to the other side of the relay switch, and the relay power pin. This way, when you hit the horn button, the constant power from the green-orange wire is powering both the relay's switch, but also the relay power, which is then ran all the way up to wherever your horns are. Presto, amperage protected, simplest wiring conversion possible for aftermarket horns on a 60. I stuck the relay down in the DS kick panel as there was now tons of free space in there.
