Ugh... unfortunately from the pictures, some of the cloth is blocked by the seat rails. But personally I'd recommend renting a Rug Doctor cleaner with the upholstery attachment. That'll really deep clean the seats and what floor cloth you can get to, at least. Then, you can go ahead and clean out the rest of the Z's carpeting as well. Better yet, you can keep the rental around to clean out the carpet around the house too, and watch in awe the sheer amount of dirt you remove
Make sure to also buy some of the cleaning solution - it'll really help with the cleaning and provide a nice scent that isn't too "chemical."