I'd like to add a roof rack to my cap using Thule rain gutter feet that I already own. I have seen a number of trucks on the road with artificial rain gutter rails that span the whole distance of the cap, but when I looked for them online, all I found were the brackets (part #542). I contacted Thule customer service and was told they only make the brackets. But, I've seen at least 6 trucks this week with the rails, so I know they're available somewhere. Can anyone point me in the right direction? Thanks.