[GuidoK]

yeah and then you have some room to reach into the engine with your arms, through the crossframe and remove the belts.

Otherwise you have to go between the engine and crossframe.

With the airbox removed you have some extra room diagonally, but the alternator belt sits on the deep under and on the other side of course.

Of course from underneath is even more accesible, but you have to put the car on jackstands and remove the undertray. Thats work too and is mainly handy for the airco belt. The official way to remove the alternator belt is removing the upper radiator cover and remove the electric fan to gain sufficient access.