When, not If lava crosses 130...

[Super8]

TomK, Bernoulli's principle applies to all liquids and gases. I am aware the viscosity of this lava is thousands of times greater than say, water, so it is hard to imagine, but it is still liquid until it cools. Therein lies the main obstacle to overcome as it is the main point in building the diversion. Most importantly, the flow would have to remain liquid. In order to do this, you would have to create an artificial lava tube on the surface. Seeing as how there are no other examples of moving lava in such a manner (that I am aware of), no I can't give you a link to something. However, Bernoulli's principle still applies. If you search up a diagram of Bernoulli's principle you can use Pu'u O'o as the input side, the diversion causeway as the low pressure/high velocity area, and the output end would be the Pacific.
The exact same thing occurs when a lava tube forms. A boundary layer forms, cools, and the lava now has a conduit allowing it to remain liquid as it travels over long distances. It wouldn't be anything really new. Just never been done before.