U joints aren't terribly difficult. I learned how on my Jeep and have replaced every one and just finished the rear drive shaft earlier today. I prefer to use a hammer, sockets and a vice to change them out.
If you are doing the axle shafts, then you need a 36mm socket and a 12 point 9/16th socket to remove the unit bearing.
Although, a chirping sound, especially one that occurs when driving in a straight line, is likely a double cardan drive shaft. If your Jeep is not lifted, then this is most certainly the front.
Later TJs had their u joints glued in place. A propane torch and a half joint press is needed to replace the factory joints. The injected glue needs to be melted while you press.
Watch lots of YouTube videos.