Clips hold MOST of it on, with a threaded fastener on the frontmost hole of the front ones, a nut accessable from the wheel arch. Door piece requires you remove the interior door panel and unscrew it (one in the middle of the door trim strip), and another at the very back of the rear one accessable from the trunk.
All that said, the "new" aftermarked strips are ill-fitting (loose on the body "snap" buttons) and require you somewhat deform the buttons. For right now, I'd say save your money and live with the dents until there's a better replacement.
Just my two-cents' worth. /ubbthreads/images/graemlins/grin.gif