Quoted from NYP:I've never tried sanding cabinet decals off, I use a heat gun and a scraper. Anyone have opinions on which way is better?
It all depends on what you're dealing with. Prior to the early 90's or so, the artwork was screened directly on the plywood. Then, Williams started using plywood with an outer vinyl material installed from the manufacturer and that's what the artwork was screened to. Most people think this is a decal but it's truly not. I think the only games that got decals installed were CC and MB. On these, the artwork was screened on decal material, then the decal was installed on the cabinet. It's one reason why most of these games had wrinkling issues.
What they used doesn't follow a timeline either. While IJ was made before AFM and has the vinyl material, AFM does not. And some games had the vinyl material on the head and not the bottom cabinet and vise versa.
I've never restored a TAF that had the vinyl material. On this one, you can see in the pics the ink slowly being sanded off. There was no glue involved. If the white had been vinyl, I would have that to deal with.
If screened on wood, I always sand it off. If the vinyl material is used, I'll remove with heat and putty knife and then sand. I've never tried any kind of liquid and never will. I'm too afraid it would drip or run onto the inside or outside of the bottom and cause a stain. I spend too much time making those look nice to have that happen.
I've got more detailed info about artwork about half the way down on page one.
https://pinside.com/pinball/forum/topic/ij-restoration-started