musky smell from air conditioner

I cleaned the evaporator coil with foaming ac coil cleaner and rinsed it well. The smell is still there, but not quite as bad. I need to get rid of it completely though because my wife has asthma. Is it possible to remove the evaporator so that I can access the squirrel fan and drip pan area. Also there is a large styrofoam block around the fan that I would like to access and remove to have access to the fan blades. I would like to be able to access every part of the system that contributes to air entering the camper and clean them, possibly even the duct work. Does anyone have experience with this?