How do I remove the rocker cover I all the screws & bolts removed and the part on the fender and under the door is off the body but I can't figure out how to get it off from behind the door

 

There is a bolt/nut down in the bottom of the speaker opening. Two ways to access it are to remove the rear speaker and reach in as far as you can or you can remove the rear seat to access tape covering a hole that provides access to the nut