Years ago at one job we used to use a combination of a razor scraper and Goof Off and it worked well. It was on pricing stickers on metal painted with enamel, and as long as you didn't dig into it and just worked it loose it would come clean. Goof Off is a harsher chemical than Goo Gone (I think toluene or some mixture) so not the best for long term exposure, but that was then and we had some ventilation. I also think the product sold now like so many might be more diluted and not the original.

Olive oil on the other hand works surprisingly well if it can get to the adhesive.