Apple Cider Vinegar Rust Inside the car

[YodaBird]

I've been putting rags of apple cider vinegar throughout the car for three months due to, if you've read my squirrel problem thread. I've noticed that rust is forming in areas, I have decided to stop doing this but with some elbow grease it comes off, but some areas are extremely hard to remove. Can this cause damage to areas that I can't remove to the car ? Can it get though the carpet of the car ?

As for the squirrel problem; I'm planning on finding a solution, if I can find a solution, until I move which is the best solution !