Many people assume the original paint on these antique cabinets was cream color. More than likely, it was white and is covered with years of smoke. Smoke is basically grease.
You can easily remove years of Smoke and Nicotine with a good degreaser.
I was sitting in a parking lot a few years ago and I saw someone carrying cases of yellow liquid in spray bottles out of a dollar store. I went into the store and found the item. It was $1 and it was Totally Awesome.
I have used it on lawn mowers, car engines, and many other hard-to-clean items.
You can also find it in half-gallon concentrate bottles at many large home / lumber stores.