Also, in the Pinball Compendium sticky, there is this:
https://pinside.com/pinball/forum/topic/bally-four-million-bc-cabinet
I actually did not have any luck with that product on my last cab, and will be using my favorite, CitrStrip as per (4) above.
Last time I used it I did a small amounts on the side and left for various times - but I was actually only interested in revealing the original shapes so I could make stencils so wasn't worried about leaving it on too long because eventually I would strip to bare wood.
Citristip is my favorite; does not burn if you accidentally get a bit on you and low odor - but will eventually strip the whole cab! (So yes, still wear gloves and use in good ventilation)
My FlipFlop had been painted, and it all came off with just 91% Isopropryl Alcohol and rags - original paint in good shape underneath. That was very lucky and rather rare! They must have used a cheap paint to repaint it brown and green (!), thank goodness.