With 2 sides of the gasket out, the assembly comes up & rearward.

If the gaskets are clean, and a little silicone grease is applied to their inner lips & grooves, and to the outboard face of the fiberglass lip they go onto, it's very easy to reinstall them, and to remove them again. They can be hauled in the cargo area or strapped to the back of the rear seat for quick re-installation if the weather changes, or if the truck must be parked publicly.

See also:

Owner caption July 2003 · Photo 217 of 5000