That's where the hard work begins. Mine were filled with dirt, salt sand and groundup Cheerios. All mixed in with the original grease. At this point you can do about half the track, or if you remove the seats the whole thing. I had them out to make it convenient for the detail shop to shampoo the carpet.
I sprayed degreaser in them and then wiped them out by dragging a paint stir stick wrapped in paper towel. Took an hour. Much better now.
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