@T_Wag I had you test that surface with the alcohol to tell me what you are dealing with. Whatever it is will not come off easily with "strippers" if it budged with alcohol. And you want to avoid the tough strippers if you can anyway because they can stop new stain from adhering. If the color shifted with alcohol, then you are probably dealing with Shellac or even old versions of thin milk paint under shellac. Typical Strippers will just make it gooey if it does anything at all. (Milk paint won't even budge with regular strippers like citristrip or EZ strip.)
Luckily, you just told me denatured alcohol, rubbing alcohol or hand sanitizer will work. (You can even use grain alcohol, which is the cheapest of them all.) I use the hand sanitizer because it spreads nicely, then cover it with plastic wrap, to keep it from evaporating. The longer it sits, the more it will remove. I then scrub it with chore boy and a five-in-one. I use a toothbrush dipped in alcohol and popsicle sticks to get in the nooks and crannies. What stays behind, I do another round. And I rinse it all with water. Some people rub down final stage with mineral spirits. The nice thing about the alcohol is it won't make restaining hard.
There are also a few sites that can show you how to use ovencleaner if you are dealing with varnish or poly or even lacquer--but I'm sure it's shellac if alcohol worked. Someone on this site has a beautiful mirror she stripped with oven cleaner. But I have not tried this way yet, and I don't know what it does to future staining ability or to the wood...
Q