I have a can of stuff I bought from a plumbing supplies place, which they sell for getting stickers off sanitary ware.
It's called MYKAL DE-SOLV-IT fast dry precision cleaner.
It's absolutely brilliant for removing stickers and gluey residue, though I have to caution that I've never tried it on car paintwork.
https://www.cromwell.co.uk/shop/lubrican...leaners/f/40349
