the sideskirts are held on by phillips screws into the sills,once you remove the screws the skirts pulls up off a rail on the sill.
the front arches are held on by 4 or 5 nuts and a screw through the sill.
back arches are held on by rivets which have to drilled out.
both the front and back arches are also held with a double side'd tape.
be prepared for something to break and the probable need to drill the screws holding the sideskirts on.

i did all this to mine when i had a bare metal re-spray last winter.
also dont be suprised when the cost of doing it spirals rapidly