When you say "Already Installed", do you mean the LED light indicator AND the ECM Re-programming? If both then:
To shift the transfer case into neutral for towing:
1. Securely attach vehicle to towing vehicle.
2. Start the engine to make sure that the battery is sufficiently charged.
3. Vehicle must be at a complete stop and shifted into 4 X 4 AUTO.
4. Place the automatic transmission shifter into NEUTRAL.
5. Turn the ignition switch to the Off Position (i.e., Steering Not Locked).
6. Neutral tow light will initially go through a bulb check, and then turn off.
7. Depress the brake pedal and press the 4 X 4 AUTO pushbutton; hold both for 5 seconds.
8. The neutral tow light will flash; then stay on to indicate the transfer case is in neutral.
9. Leave the ignition switch in the Off Position and the transmission shifter in NEUTRAL while the vehicle is in tow.
DO NOT DISCONNECT TOW VEHICLE BEFORE PLACING TRANSFER CASE INTO GEAR.
To Shift Transfer Case Out Of Neutral After Towing:
1. Make sure the vehicle is at a complete stop.
2. With the brake depressed, turn the ignition to ON (Not START).
3. The neutral tow light will turn off to indicate the transfer case is out of neutral.
4. Start the engine and shift the automatic transmission to DRIVE to make sure the vehicle is out of neutral.
5. If the battery is low/dead or the vehicle does not shift out of neutral set the parking brake until the vehicle can be serviced.