Hi, Chris,
There's a faint possibility that this may be a game (or playfield from one) that I unpacked when new. It's really only a suspicion, but I notice in the playfield pictures that the bumper and slingshot coils were/are each positioned away from the coil stop on their bracket. That was something I always did, especially after catching the terminals of a coil on the cabinet while sliding out the playfield of a High Speed II.
Re. the damage to the line filter box; that may have occurred at a later date, when some hoon wanted to remove the u.k. socket and mains lead which we added to each game. The square black plastic 'blank' is missing from the box too, which was where the extra lead emerged (AIR, I'd open out a small inner section of it)
Other points with games I'd prepared were insulation tape on some of the coil brackets, such as knocker or outlane kickback, and a total lack of coin meter (and its wiring)