Don’t use chemicals! They will take the finish off but they will also melt any plastic binding or rosette. I had a guy who ruined one of my guitars by using methalyne chloride to remove a poly finish on a nice acoustic. He melted the binding and the rosette. Don’t use heat guns either. I did another one of my guitars with this and i burned the the wood on the back. There is only one way and it’s sanding. You must be very careful. It’s risky as hell but the sound is way better without the heavy polyester polyurethane finish.
https://youtu.be/a_MO6Q1bTPo