Many people on this site refer to their outboard as being a stock motor. Example OMC Formula E , Yamaha 70CES , Yamato 80 etc. in a stock motor race class each motor has a Document with all of the spec measurements of that motor. To be a legal motor, motors must pass inspection. This is the inspection process for a STOCK class motor. Most inspectors are very familiar with the motors they inspect. They usually have special tools and templates to help in the inspection. The decree to which the motor is inspected depends on the event. National title and World title events will have complete engine tear downs and multiple inspectors to verify the legality of every part of the motor. The inspectors check the simplest parts first. Most times the inspection process stops with the first failed specification. The motor is disqualified. In this video the inspectors are doing the disassembly. At a race a member of the race team does the disassembly. MOD classes have less inspection because those motors can be modified and don’t have as many parts that must be to an exact measurement.
https://www.youtube.com/watch?v=YXhcu1p4SlU