Dave,,to remove that trim piece,with the door open,you must pull back the weatherstriping seal.Behind the seal will be some phillips head screws set every few inches apart.Firts you must remove the one that holds the weatherstrip moulding and then there should be more srews that hold the drip rail molding below that.Then it should pry off,but make sure you've removed all the screws as some can get hidden below buetal that they used in this channel.Be very gentle with it as it bends very easily.