how to change out the bulbs in the instrument cluster?

You must remove the cluster to replace the bulb which will be at the rear mounted to the circuit board. Here are the instructions so you can get the job done.

LTD and Marquis

1. Disconnect battery ground cable.
2. Disconnect speedometer cable from cluster.
3. Remove instrument trim cover, then the steering column shroud.
4. Remove shift control cable clamp retaining screw, then disconnect cable loop from shift cane lever pin. Remove plastic clamp from steering column.
5. Remove the four cluster attaching screws, then disconnect feed plug from receptacle.
6. Disconnect engine warning lamp, then remove cluster from vehicle.
7. Reverse procedure to install, noting the following:
a. When reconnecting shift control cable, place loop of cable over pin on shift cane lever.
b. Position shift lever in Drive, then rotate cable clamp until indicator pointer is centrally located on D. Torque cable clamp retaining screw to 20-30 inch lbs.
c. Move shift lever through all shift positions and check indicator pointer for proper position.

Let us know what happens and please upload pictures or videos of the problem.