A schematic shows logic, not the actual wire runs
A wiring diagram shows physical wire routes; an EM schematic shows how switches and coils connect logically. Two parts joined on the schematic may have no direct wire between them in the game, so trace by wire colour and part labels rather than expecting a single wire.
Systems
Source: Repairing Electro-Mechanical (EM) Coin Operated Games to 1978, Part Two, Clay Harrell (pinrepair.com)