With 01 I dont think it had the amp option it should make it pretty straight forward. Im assuming its an aftermarket so you should have gotten a harness adapter and pre wired the unit. Then right behind the front window you have to take off the defrost vent cover its either 2 or 4 screws I believe mine are long gone. Be careful prying it up its pretty easy. After thats off the stereo surround has like 2 screws on top. Your going to have to take your Jeep out of park to get it out of the or shifter if its in the way mines an auto I dont know about a manual. After that there are 4 screws holding the radio in take em out. Pull the unit out unclip the harness from the back might be kinda tight also pull out the antenna.
You will have to have an adapter for the antenna as well. Plug your antenna into its adapter and the harness into its adapter. Stuff it all in there and reverse the procedure.