If you have large heavy panels, you'll probably need to make your own brackets for them. What is adequate on a house is rarely adequate at highway speeds - how many houses can do 65 MPH? Most ready-made brackets for PV panels are wholly inadequate for a moving vehicle.
The reason to have tilting panels is to maximize solar harvest in marginal conditions, such as in northerly latitudes, and/or in winter, and/or in less than perfectly sunny days. Those are the times that you want to squeeze every last amp of power from the panels, and even a simple longitudinal-axis tilting mount will significantly increase power production at times like that. This short article explains it better than I can:
Optimum Tilt of Solar Panels The State data tables also show the actual gains for selected locations throughout the USA:
https://rredc.nrel.gov/solar/pubs/redbook/ After I read just these two sources of data I was sold on the idea of a simple one-axis tilt for my bus, and I have no regrets doing it that way even though it was a lot of work to do so. I winter I anticipate my 2kW of tiltable panels will equal or exceed the output of a much larger fixed array; it will be nice at times like that to run my heatpump for some free heat!
John