Lay that carpet on the drive wayu and pressure wash it carefully, or at the carwash.
Then spray with foaming carpet cleaner, scrub with a stiff brush, and hang on the fence to dry.
Like new and will still retain most of the custom fit shaping.
I personally don't care for bed liner on anything except a truck bed but it should give yopu insulation and tyou can run the carpet over it if you want to.