You could try a heat gun(not to close)it will soften the adhesive.
Then use a razor knife(scraper),it's actually a razor blade in a handle.
We use this method for taking off stickers that are on the side of doors and handrails which are bare wood.
If you just try to scrape them off it does make a mess.
using the heat gun with the razor blade they come off real easy,trick is to push the blade slow under the sticker or tape.
Works excellent and no marks or residue

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