Military Dune Buggies (Land and Sea)

This book is about a vehicle called dune buggie and they are used to be a vehicle for spies. But they had a problem that this vehicle was weak and was destroyed easily by the enemy. So they improved it and now it has a gun that is strong. The second problem was that the tires are not good for the sand and it gets stuck. So they changed the tires. This vehicle has three people in it. 2 people was in front and the another was on top. the top guy uses the weapons and the 2 people at the front controls the vehicle.