Can you check if the guide supports are already in the box?
Tischer had 4 different prices depending on your build date and if your car had or did not have ZSP.
That's why Tischer charged $210 more for the kit used on ZSP installed cars built before 06/2006.
Otherwise, there's no good reason for the different prices that Tischer charged.
Original Tischer post
btw, can you PM me the price to ship to San Francisco, Calif ZIP 94118