Cross Country Tail Light

Anyone know how to access the turn signal/brake light bulb on a 2005 Cross Country DP? The lenses are round and have a rubber gasket around the outside. It is almost impossible to even reach them from the inside of the coach body. I'm hoping I just have to remove the gasket to see how to get to the bulb. HELP! :question:
Cross Country Tail Light

I don't have this unit but if it's similar to the newer buses that I drive for a living (not for much longer) then you just have to pull the unit out by the gasket. It 'pops' out.