Bought a shopvac, and claw attatchment today. Going to pull the front seats, vac out all the crap, then attempt to clean the carpets tomorrow using woolite/water. Few questions though 1. I've seen a few different woolite/water ratios, which is the best to use for some pretty set in stains, on gray carpeting. 2. Should I use some type of brush to scrub at the stain? or do I just spray, let soak, then extract?