i am not sure how close to realistic car production you are aming to get the game.
IF you are planning to make a more realistic game somebody should have a look at the logistic part of the game. To be honest, i am a software developer, working on warehouse manegement systems for 9 years now and had two projects with production line suppliers for car production, so i might be a bit to critic about this
Compared to the real life, this is fun, but pretty much wrong an inefficient.
My main issue about supplying the production line is currently the “Fit Door Panel Slot”. If you have all technologies applied, it will need 10 units per car as supply with an on site storage of only 16. Car production is meant to be just in time, but this is a bit to much.
My first proposal would be, to create stacks of ressources. At least for small parts like: chips, sensors, Alarm systems etc.
If you would like to be closer to real production lines, you might want to have a look at kanban. Which origins from car production