Got the XJ PDC in, along with the JK fan connector pigtail. The pigtail I ordered was actually for a '10-15 mustang, way cheaper on eBay than the ones for a JK, but it is the same connector.
After a very tedious time, it's fully disassembled:
The plastics are extremely brittle and I ended up breaking a number of the plastic tabs. Glad I got some practice in before messing with the TJ PDC.
Here's a before shot of mine, just for reference:
As you can see here, I've got 5 empty maxi fuse slots. I wanted to make them all available for future use, so needed to insert some connectors.
After carefully prying the bus bar out the back, I popped in the missing connectors down the middle two rows. The outside rows are added in with the wiring, which I'll just add when needed.
Next, wanted to swap one of my 2 slot large relay inserts for a 4 slot small relay insert. I wasn't able to get it past the wiring, so I had to de-pin the last row as well.
You will need to file off this tab from the PDC frame to fit in the different relay configuration
Next, since the starter relay was already de-pinned from the end, I wanted to convert it to a small relay like you see on later TJs and also relocate it. I'm not sure what the current requirements are for the circuit, just assuming it will be fine since it is on later models.
The connectors are different, so I needed to snip the end off the factory harness and add in one of the harvested ones from the XJ. I (carefully) ripped the connector off the wire.
Then I soldered it onto the factory wire. I don't generally like to solder automotive wires, but none of the harvested wires were close enough in wire size to just use a butt connector. I had heat shrink on there for strain relief, but I had to cut it back off for it to fit in the fuse box.
Got the relay moved to up near the mini fuses. Zip tie so the wires share any strain. The other wires in the background with the blue tape are for the rear window defrost, but I don't use that so I'll just insulate the contacts and tuck those wires away somewhere.
As careful as I was, I still broke two plastic tabs when inserting the connectors to the housing, so had to load them up with some hot glue. Seemed to be adequate to get the relay plugged in though. I used butt connectors for the smaller trigger wires.
Got the box reassembled enough to test that the Jeep still starts, and it did!
The two big relay spots will be used for low/high speed fan relays, and that leaves me with 5 more slots for other things, like lights or air pumps.
Overall I think it will make it so my PDC does everything I will need it to do, but I can't say I'd recommend this to others. The plastics are just so brittle you're likely to screw something up, like those two contacts that are only held in by hot glue now.
That's definitely enough for today. Still trying to wrap my head around the best way to wire up the fan.