> When does this become an issue when you and Caterpillar have regulatory obligations for the operations of that equipment with regard to emissions, OSHA, MSHA, etc... ?

why would this be an issue for software, but not for the car-modding business ? if you can "trivially" find the materials and guides to add a turbo to your car engine (https://www.torquecars.com/tuning/adding-turbo.php), it's very hypocritical to mandate different rules for software running inside of it.