Another roof rack option that I just came across is the Yakima MegaWarrior (#8007080). It's LxWxH dimensions are 52x48x6.5.
At first I thoght "damn, whats with the short racks?" then remembered that Yakima has extension kits. Add on p/n #8007082 which is a 22" extension and I'll be sitting at a solid 74x48x6.5. So other than custom built by our forum local, the Yakima looks pretty good as well. (Price isn't that bad... $315 with free amazon price shipping, plus another $120 for the extension. So around $440 said and done definitely makes it a solid option)