In my carsOwners table I have a complete list of all owners and cars without repeating.
The complete listing of all owners is in tbl_Customers, no? You have set up your database properly. My point is that your current tbl_CarsOwners has information about the cars, one of which is OwnerID and the owner details are in tbl_Customers.
Anyhow, at the end of the day, it's your database and you can call your tables anything you want.