One more thing, if this thing really addicts you, keep an eye on ebay auctions for racing harnesses that bolt on to stock seat/seatbelt mounts. I have a Schroth Rallye-4 and love it, but you can get the (much) more affordable Sparco etc. ones for a fraction of the price. (I like that you can unlatch the back of the Schroth and "hide" it behind your seat)
