I have a Yakima Whispbar rack on 2010 Ford Flex and it came with the clamp style fit kit. Since then I have read threads on many forums about Yakima tower type racks that can mount directly onto existing roof mounting points. I have also looked through the Yakima Whisbar fit kits and don't see any reason why I couldn't use a K368 or K371 fit kit and install my bars directly on the factory mounting points and eliminate the clamps?? Has anyone done this? Any advice would be appreciated. Thanks