I picked up this 1976 Gottlieb Target Alpha at a garage sale. Great back glass. Playfield may have never been cleaned. I hit it with some Mean Green. That may have been a mistake. The art is intact but I may have stripped off some varnish. I'm thinking it's a good candidate for clear coating. Needs a few minor touch ups. Has some minor cupping of inserts. I'm thinking of touching up the paint but leaving the inserts as is.
It still has some dark dirty spots and a few ball swirls. What do you guys use for cleaning the dirt and grime off a playfield from this era?