Congratulations on your achievement!
The work options that you mentioned will completely depend on your interest.
Working in car dealership would involve you to talk to various customers and convince them about the services at your center. While working with manufacturing firm will require you to focus on machines and complete the given target, of making spares or machines in stipulated time.
Both will include working with targets and timelines. But it would certainly require different kids of personality traits.
Hence you will have to make a wiser decision.
Its advisable that you talk to people working in both the field and get first-hand information on what are the pros and cons.
How this helps.