I did my 99XJ last week and it was a simple upgrade. There are two stationary large plugs (kinda like a USB plug on a computer) in the dash that the cluster simply pushes into and your plugged in and ready to put it back together. Just make sure to disconnect the battery and wait a few minutes before going to work on your dash. The sensors for mine did not need changing and everything works great. There were several slightly different clusters made and I bought one for my year and build date on the door but I don't know if it makes a difference or not. It is so nice having guages instead of lights. Even the door open including the back tailgate ajar lights work correctly along with everything else, cruise, highbeam, airbag, turn indicators, etc. etc.. It is especially comforting knowing water temperature. Don't forget to disconnect the battery for at least 2 minutes while the airbag system goes to inop mode. I had the new and old cluster sent out to a dealer to fix the speedometer difference but they botched that and put the wrong miles on it so that was a waste of time and money.