I prefer to use a very thin guitar pic to get under the edge of badges, bezels, labels, lenses or anything thin or brittle because the pic has more surface to prevent a bend or stress cracks unlike a screwdriver. You can get assortments at guitar center, best buy, ebay or any music store.
Once I get under it I switch up to a thicker pic for more stubborn adhesives or those 3m foam backings, which can be a real pain. The heavier pics give more leverage when you need it & sometimes can distort foil badges but when used with fishing line or a guitar string it would probably work the best.
The glue is usually dried up after 20 years or so, so once you get it to lift the rest usually peels up effortlessly. My method is to take two pics & walk them along the edge, works well for me.