'98-01 Trooper S models are your source vehicles. If you get a '00-01 you'll need to source the ECU separately since the later models have a different computer setup. Easy to tell though as the correct ECUs are located where our are under the dash, the wrong ones are in the engine bay.
Wiring is actually pretty easy. All you need to do is jumper out the thick wires at the mode switch connector M-25 1 to 4 to bypass the need to have the brake on when starting. Hook up the reverse light switch on the AR5. Connect pins 1 and 12 of the cruise control module through the normally closed clutch switch.