hmmmm ... ingenious, woody. Where can I get suction glass holders? I'd need more than one to realign the whole cupboard back.
big-all, I'm thinking about your suggestions, and thank you, but please remember I am a woman and don't have your confidence, experience, and testosterone, no matter how delicate the drilling. The backing sheet is very thin and bent out of shape. I don't trust myself with a drill to achieve the desired effect.
Why on EARTH are the cupboard backs so flimsy, why are the grooves so shallow, why aren't there already finger-holes in them, etc, etc???? This must be a maddening problem to many many people.