This appears to have an early production SS. The guy on the #3 of the Stiff-O-Meter is a different guy than the regular production model (I like this guy better). It also has an apron with the spiders on it. I bet the "Electrifying" lettering in the pop bumper pit is green instead of the production white.

Some early production SS machines also had a difference in the cat art on the insert in front of the "Saved By The Spell" stand-ups, and a difference on the outlane insert that said "Saved By The Spell". I don't see the "Saved By" above "The Spell" letters in these pictures, so I wonder if this is a transitional playfield that falls in between the prototype/early production playfields and the regular production run.

It would be interesting to see the last numbers of the serial number as I bet it's within the first 40 or so produced. My SS has a serial number in the 20's and it has the different guy in the #3 spot, green pop bumper pit lettering, the spider apron, the different cat art, and the "Saved By The Spell" lettering. There's interesting differences in the early SS run if you're into that sort of thing.