Hi together,
The First roofs are placed to See how much roofs plates are Missing and If the Drive below the roofs plates will work.
In this case the dimension was a little bit tricky, as is is no longer on goggle maps available. In this case I have a picture of a V60 and in the background several parts of the storage. I took the length over and find the dimension of the first storage room. The height came out of the height of the wagon and was done via interpolation.
I was lucky as you can see the car took place below the roof.