William,
You did not say what kind of 03 coach you have. If it is a 2 slide Marquis, the control is located behind the inverter control on most coaches, bat a three slide coach will probably be located in the location pointed out by Rod.
Why do you want to access the control? The controls were hidden to prevent owners from misadjusting them and causing damage. If you are going to replace the wind sensor, just unbolt it, pull it up with about a foot of wire and cut the wire. Then use butt connectors to attach the new sensor, attach the new sensor and reseal it.
Gerald