It may be secured in the same manner as my 2002 Suncruiser. Mine were screwed to the bottom of the overhead cabinets. It's a little difficult to find the screws since the heads sink below the fabric inside the valence. I don't remember if they're magnetic but, if they are, a magnet will help. If I recall, I located mine with a thin bladed, flexible metal spatula made for icing cakes. I was able to slide it between the valance and the cabinet and move it side to side until I hit a screw. Now that I knew its side-to-side location, it was simply a matter of probing to find the screw head.
2002 Itasca Suncruiser 35U