Just use the factory rack mounting locations located below the trim strips. You can use the instructions (PDF) for any 5th generation rack to see where they are and the hardware needed. You can find factory rails on Ebay for a good price. The only draw back to the factory rails and racks are they have a low weight limit, about 150 lbs. I'm sure the roof can take much more than that for I have see racks in remote locations that far exceed that weight.