I did get the trim off and yes it's aluminum. It's fastened with little, and I mean little rectangular clips and 3/8th nuts - both steel so naturally they were rusted together, they snapped off. Get them loose from the trim and slide them off! Something interesting - I was working from the middle out to the end (because I could actually see the middle nuts) and when I snapped off the very lower end nut, the trim came off the tailgate and it's really bowed! Got the other end off and it's bowed in the middle! BTW, the lower hinges got to come off to access the end lower nuts! The factory never even put a nut on the uppers as there is no access!! I'll have a pic or two after I let the phone charge up.