thort i would do a guide to petrol caps, i now theres one on here but wanted to do a proper one with pics,
to remove the key from the cap, grab an old knife and your petrol cap, a spear pear of hands will help but isnt a must (and for sum people on here a supervising adult)
insert the knife in betwen the white plastic prong and the metal prong like this
then just use the knife to push the 2 prongs apart(you only need to do one side of the cap), when there about 5mm apart the key will turn and can be pulled from the cap
on to removeing the body colourd cap from the lock mec,
you must have the key out for this
take your kniffe and insert it betwen the lock mec and the plastic cover
then twisting the knife (pull the knife handle towards you)with a bit of force the cap will come away on one side, grab each bit and thay will pull apart(in a braking type movement)
hope this helps a few people
any questions ell free to ask
this will be getting linked to my other guides in the stickys