So MEK Substitute...

I went out to the Home Depot today to find some of the things you recommended and had planned on getting Xylene but unfortunately due to Covid and the work force shortage the stock in my local home Depot is limited and extremely unpredictable, you can't even get an answer on when items will be replenished or if you order them online when they will show up to the store so the only xylene they had was the big can and that's way more then I'll need nor did I want to pay the price for it.

I Have acetone, Denatured Alcohol which I like a lot for thinning acrylic though it's probably over kill but it works great in my experience, paint thinner and mineral spirits at home and while they do work they weren't getting the hard to get stuff out very great.

So what was left was MEK substitute which as you mentioned is pretty hazardous stuff. I'm used to be a part time paid fire fighter and dabbled in hazmat for a brief period of time and we used to have a Nickname for certain chemicals Methyle Ethyle Death and MEK sure fits the name.

Man that stuff cleans but holy hell that stuff will kill you if your not careful. A word of caution for those using the stuff 1. Use sparingly and in a well we'll ventilated area, 2. Wear gloves, 3. ventilation be out side if possible. 4 find another chemical lol

For those of you who don't know the recommended way to dispose of this stuff is to absorb it in paper or something else absorbent and safe to burn, then set it on fire  and burn the chemical off there is even cause to add other flammable fuel to make sure your burning it off. In the fire industry we let this stuff burn at a distance because clean up of the liquid form is more dangerous in some cases.

I recommend a coffee can with sand in the bottom. Soak the left over chemical into a cotton rag or paper towels and burn it in the can on a not so windy day and make sure the smoke blows away from people it can harm.

The stuff works but it's definitely a hazard