Turtle Wax Power Out upholstery cleaner and Turtle Wax foaming carpet cleaner for the carpets and/or floor mats are what I use, and it seems to work very well....it got the grease stains out of the carpet and seat in my 93 Ranger, and I have used it a bit in my Bronco 2 as well with great results....kind of like carpet shampoo, apply the cleaner, let it sit a couple minutes then scrub, let dry then vacuum.
Years ago out of desperation I used oxyclean powder mixed with warm water to get a gigantic coffee stain out of the carper in our 96 FSB. Somebody spilled a large Mickey D's coffee, covered it up and never told me. The stain was a couple of years old by the time I saw it. It was like the TV commercial, I poured the mixture on it and the stain went away before my eyes in seconds. I ended up cleaning the whole cloth interior with it.