an absurd idea. how about making the game in unreal or cry engine or (the game engine that car mechanic simulator use)
where you have a first person character.
(engine design room)
where you assemble an engine from differents parts which are on a table.
you have different monitors where you see the test results (emission, hp, torque, fuel economy)
(car design room)
on a monitor you select a body. then it spawns in the middle of the room.
you can walk around it and that
to place parts on the body (headlights, taillights) you select them and you carry them in the first person. when you choose your place you left click and it will place it on the
(the factory)
this is where you hire workers to build that stuff. the more you have the faster they produce, but instead of workers you can have robots, but they need maintenance.
…