WOW, another mk 3 that had them on, i took mine off, they're just stuck on with a sh*t load of glue, so get a hairdryer a bit of tar remover and a card, and be prepared to spend a bit of time doing it. i presume mine were on from new because when i took mine off it left a white "milk" line all across the side of my car
and nothing will get rid of it!!
so i'd just peel the front one off, the little chunk on the front wing, and check if your paint has gone funny underneath before taking them off
heres mine, you can see the line really well on the door. if you zoom in
before
after