Paul, thanks for the link to the Monster Scooter MZ175 coils.
https://www.monsterscooterparts.com/ignition-coil-for-yamaha-mz175-f166-generator-engines.htmlI posted the original discussion about finding the MZ360 coils that work but require that the bolt slots be elongated to fit.
I had been using the MZ360 coils for several years, but I never filed enough on them to get the .016" - .024" air gap. After I saw your link for the Monster Scooter MZ175 coils, I ordered two of them and replaced mine ($20 + $9 shipping => $29 total). THEY WORK GREAT! They fit without modification and it is easy to set them to the correct gap.