An update for anyone reading this in the future...
A big sign that I overlooked was fluid on the back half of the diff. I believe that alone could have solved this mystery from the start. Also, I noticed my frame on the drivers side was looking
very clean despite me not having cleaned it...ever. So when you see obvious signs, start looking. It probably won't be hard to find what's leaking and you won't have an engine bay covered in fluid like I do. Now on to the fix...
Replacing the sensor stopped the PS fluid leak. I believe it took a 7/8's wrench to get it off, but I also used an 11/16 (or something close to that) to hold the square piece of pipe where the sensor screwed into so I didn't break anything (see pic below so that makes sense). The black plug has a little clip that has to be depressed to remove it that is on the bottom. To make it easier it get off, I turned the switch a half turn, removed the switch, then took the sensor the rest of the way off. Also, have a rag or the new sensor ready because fluid will run out of the little hole pretty quick. This is obvious, but I was in a hurry to get it done before I needed a flashlight and it surprised me a little bit. Not the first time I've had to learn the lesson of slow down and think...but I'm stubborn
Luckily I didn't lose too much fluid because I had a roll of paper towels right next to me.
Edit for clarification: this is the old picture. Didn't think to grab a picture of the new one, but everything around it was cleaned up after the install and is still clean after taking the jeep on a couple drives around town as well as testing it as I did before when I saw it leak the fluid.
Hopefully this sensor will hold up for another 19 years like the first one did. And thank you to everybody that helped me solve the problem. I learned a little bit about my jeep and vehicle maintenance in general this weekend by having to take a look around at things and actually know what I was looking at.