It needs oil. Oil will break down the adhesive and shouldn’t be hard to clean off of a sealed/finished surface. I’ve used anything from a few drops of cooking oil to peanut butter (doesn’t run!) and let it sit. Depending on the adhesive it could take minutes or hours, but typically makes removal much easier.
Ham, pineapple, onions, green peppers, and jalapenos, no sauce. One of my favorite pizzas.
There’s enough goodness that you really don’t need pizza sauce on it, or at least I’ve never come across a sauce that works with pineapple. But the flavors and textures work well together.