Does anyone know a quick-fix to level the strings on the nut?

It’s a 2’nd hand parts-caster made from old Fuji-gen parts, and I’d really like to avoid removing the old nut (it’s not coming out easy), was thinking to try giving it some epoxy or super-glue in the slit for the D and B-string, but I’d love to hear any ideas before I start destroying one of my guitars :-)