You will find it difficult to locate any information regarding installing solar panels on a motor vehicle of any type for the purpose of providing charging current for motive use.
This is related to the extremely small output per unit area of a solar panel and the extremely high power requirements of an electric motor vehicle.
Additionally, solar panels require optimum angle to the sun to provide rated power. Panels attached to a motor vehicle will not provide for that angle without additional mechanisms, additional complexity and additional weight.
Our house is equipped with 11kW of panels, but again, that rating is valid only during a limited period of clear skies when the sun is at the highest. The 43 panels may produce sufficient power to charge our EVs (only one at a time) if no other electricity is required for the household and only during a limited period of time.
Consider that the roof area of a 1500 square foot house is substantially larger than that of a typical motor vehicle (semi-trailers and coach-class RVs not considered) and the power produced is not likely to charge the typical EV.
You will find an EV here and there with a solar panel integrated into the roof. This is used to provide charging current to the aux battery (12v) that keeps the vehicle computers running, along with other related accessories.