This locally produced product is the best I have ever used, AND it is non-toxic and safe to use indoors and on food service surfaces. Pretty cool! I've used it for odd instances I would never have thought I would use a gun solvent product.
https://mirachem.com/info/?page_id=88&ProdT=25.00
I had a friend who bought a whole bunch of used restaurant stainless steel appliances at an auction, but the lame brains marked prices on them with permanent markers. We tried everything to get that schit off. Finally used my Mirachem gun cleaner on it, and with a little elbow grease, took that stuff off cleanly.
And this stuff lasts forever. I got my sample gallon from them nearly 20 years ago in a promotion they were doing on the internet. I pretended like I was some sort of gun shop, and they it to me for free. I wasn't trying to get a damned gallon, but that's what they sent, so,...ok. I'm not even halfway through it.
I've recommended this to friends in the past, but it wasn't always available. I think the company went under during the 2008 financial meltdown,...but it appears they were rescued and are back in operation.
Brownell's carries it, but is out of stock at the moment.