I did. I also have light gray carpet and it did work wonders for a few grease spots. It actually worked wonders for everything except that rust spot. The carpet looks normal (not matted or stuck together)- just rust colored. I scrubbed the heck out of it, and it really didn't do much.
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98 S10 Blazer LT
192,000 Miles
4 door 4.3L V6