As promised here is a full write up on the trans temp gauge.
Starting with the parts you need:
Gauge - pt#8349 This is actually a GM factory specific gauge that happens to match the 97-01 Cherokee cluster perfect. It has almost identical font and is green colored backlit and has an orange needle. If wired correctly it will dim with the factory gauges as well as mine does.
A-Pillar mount - pt#15211 This is for the single gauge pod Cherokee specific.
(For 97 or older) Adapter for the sending unit - pt#2267 This is a 1/8" NPT to M14x1.5 adapter.
And obviously wire and connectors. (I chose 14 gauge)
The A-Pillar mount comes black but I painted it with the closest matching paint to give it a more factory look. I used a satin light grey.
As for the wiring.... the gauge has 5 terminals that need wired.
1.Ground to power the gauge
2. Ground for the light (I jumped mine together as you can see above)
3. Power for the light. I tapped into the 3 switch panel in my center console for this. You need to find a DIMMER wire if you want the Auto Meter gauge to dim with the factory interior.
4.Power wire for the gauge. I went to an ignition hot source in the inner fuse panel for this.
5. Sending unit wire coming from the sensor in the transmission.
Here is a picture of where I installed my sensor. I want to stress that only a 97 OR OLDER Cherokee can do this. On the 99-01 AW4 Transmissions this plug is actually casted over. In that case you will have to cut into your hot line and add a sensor there. Which means you will not need the py#2267 adaptor like I did.
I chose to remove the plug in hopes of a more accurate PAN temperature of the trans. Like an average between the hot and cold line if you will. (It is a T-55 bit.) It was a very simple process and allowed me to avoid cutting into my trans lines (Which I already had anyways for the cooler lol). This is what you need the adaptor for.
The finished product! Feel free to ask questions!