They are easy enough to remove, but if they've been on for some time they normally leave a mark from where the paint will have faded everywhere else but not under them.
How do you know Zeb will like flowers and bees? She might not be a flowers and bees type of gal!
If I put flowers and bees on my car, he would refuse to start! (Actually, given that he's been stuck in the garage and not started for 6 months he may refuse to start anyway).
plonk them on with a bit of blue tac or summat similar to see if you and Zeb agree on the deisred effect. If neither of you like it, just whisk it off. No harm done. :-D