Build and in(side) car bike cargo carrier

I like this idea, too bad the author didn’t do it for a 4 bike car rack.  Not sure what kind of car is used, but I wonder if I could do this with a Scion xB….I have PVC pipe, wood, casters….not sure on the fit, yet.

UPDATE: its some sort of VW wagon…

http://www.instructables.com/id/In-Car-Cycle-Carrier/