I pulled my side skirts off to paint them and found a little trick to get the plastic rivets out. I used a little flathead screwdriver and a pliers to hammer the center in
only hammer it in about 1/2" so you dont pop the center pin out and into the body
then wiggle it while steadily pulling it out. i only had 2 that the screwdriver pulled out of,just used a pliers to finish pulling them out.
the tops have a bunch of push-in tabs. I found that if you hold them (skirts) from the bottom & push them in and then lift up you can pry them off/out.
theres a bunch of 'em. here you can see the shape so you can get an idea of how to move them.
pull gently and wiggle, i ripped some of the tabs off my 1st one
since i had no clue what i was dealing with