There are all kinds of ways to do it, personally I thought a system installed between and parallel to the hwys in the AZ, NV, NM desert would make install, maint, and power delivery easy. I would imagine much of this land is already owned by the government too. The article suggests it would take $420B over 40 years (about the cost of the average war).
I say how can we not do it and start such a project now. I also say tax all imported oil to finance it. A 3% tax would provide $14B/year. There are questions about enough resources to produce this quantity of panels though.