Factory Roof Racks

I was planning to get the factory roof racks since I like the looks and the design of how they fit to the roof.  One BIG problem... the distance between front and rear rack is only 24 inches and this is pre-set with the factory.  This is not optimal when carrying larger items(in my case a 9' surfboard). 
Got absolutely no ideas from the service manager at a MINI dealer about increasing the factory sets(even 3' would be better).  I will assume that these factory mounts are designed to attach to a framing component.
Has anyone had any luck with mounting the factory roof racks wider than 24" or will I need to go to a outside vendor.
Then, what kind of issues do I face with attaching to the rain gutter area(e.g. Thule)?
 
 

YOu should google it, I would go aftermarket.
 
http://www.orsracksdirect.com/yakima-sailboard-surfboard-racks.html
 
Good luck.
Krafty