@rotodave suggestion is quick easy and foolproof, if not permanent .
If you are adventurous you can remove everything from the playfield , clearcoat it , apply decals and do minor touch ups , clear coat again , sand and buff to your liking.
Vid describes all that below .
https://pinside.com/pinball/forum/topic/vids-guide-to-ultimate-playfield-restoration/page/6#post-888283