To fix that, we will strip out the interior, and then wash the metal with mild bleach and disinfectant. Same thing for the outside, after which we use a clay bar to smooth the paint, and glaze and wax.
In the image above you see rodent droppings all round the wiring, but by great good fortune, the little beasties left the tasty braided harnesses alone. This owner is lucky. So is his insurer.