radiators are really easy and pretty straight forward to do on the 2.5. once you get the fan shroud out of the way, there's SO much space to work with. and i don't know about the temp sensor on the 2.5, but on the 4.0, you really need to take the valve cover off in order to get any kind of wrench on it. so you might have to do that with yours, but i'm not positive.
My personal feeling is you can never go wrong adding a couple of wraps of teflon tape.
The other things I would do if you are going so far as changing the radiator is to be sure to install new hoses (both radiator and heater). For a little extra time and a few bucks it could save you much potential grief on a trail in the boonies!
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