Amishcellphone said:"A unit will consist of several Infantry models or small vehicles that fight as a group, but it can also be a single very large and/or powerful model, such as a battle tank(or grav ), a monstrous alien creature or a lone hero. In the rules that follow all of these things are referred to as units." Period.
It's very clear that page 8 of the BBB states that vehicles are units. Therefore, you can Guide vehicles.
This is debatable, he can only cast powers on himself, the unit he is attached to, or the vehicle he is in (I'm not even sure about the last one, but it's almost like an attached squad) he cannot cast spells outside of the vehicle, such as mind war or eldrich strom because he has no LoS to anything while inside the vehicle. If anyone can clarify page numbers for casting powers on a vehicle while inside it would be helpful.Murekhalir said:Yes, And if to say like a farseer is in a waveserpant, he may cast the spell inside the vehicle.