No, I don't believe you can satisfactorily use a vehicle-mounted pipe for the Interet satellite system. It won't be stable enough. It has to be rock steady and 100 percent level in order to locate the satellite and hold the setting once you've gotten it.
That, likely, would work for the little satellite TV antennas, but not for the much larger and much more bulky Internet dish with its three-axis mounting hardware and all.
This address will take you to some pictures that will give you some idea of size and complexity.
http://www.globalsatsolutions.com/ Once at the site, click on "Tripod"