If you have the same 2 sided light fixture like mine you need to slide the lens cover out (away from center of fixture) about 1/4-1/2" then it comes down.
On some light covers the tabs are released by squeezing the sides toward the center of the light.
__________________ Happy Camping! ///// Richard D.
2006 4x4 Ford 250 SD / 2007 Flagstaff 827 FLS
One very patient wife and one furry child who travels with us. Forty-two years of trailering and camping, and I still have a blast.