All you need to do is install the Yakima RailGrab roof rack system to the 2005 Subaru Outback siderails. Be sure to selct the 58 inch length crossbars with the Yakima RailGrab roof rack system. This will allow enough room on the crossbars to attach two sets of kayak racks next to each other.
Now for the kayak racks you will want to get 2 pairs of the Yakima Mako Saddles and 2 pairs of the Yakima HullyRollers. You attach the Yakima Mako Saddles next to each other on the front RailGrab cross bar and the 2 pairs of HullyRollers on the rear RailGrab crossbar. You are now all set to lift the front of the kayak only onto the HullyRoller and then lift the back of the kayak and slide it into position onto the front Mako Saddles.
Another really cool accessory is the Thule 854 Water Slide Mat. This mat attaches to the rear crossbar and lays down over the rear of your car. There is a non slip underside. The Thule 854 WaterSlide mat both protects the surface of your car from contact with the kayak and also helps even more to easily slide the kayak up into position on the kayak rack.
Yakima RailGrab roof rack system
http://www.orsracksdirect.com/yakima-railgrab-roof-rack-system.html
Yakima Mako Saddles
http://www.orsracksdirect.com/yakima-mako-saddles-kayak-rack-8004037.html
Yakima Hully Rollers
http://www.orsracksdirect.com/yakima-hullyrollers-kayak-rack-8004035.html
Thule 854 Water Slide Mat
http://www.orsracksdirect.com/thule-854-water-slide-mat.html