How do I adjust my wind mirrors?

This might sound ridiculous, but I have just bought a TD5 defender and need to adjust the wing mirrors. All I want to do is turn them slightly to get a better view. But they are stuck solid! Is there something I am meant to loosen or is it case of covering in wd40 and keep trying?

Grab with both hands.. it may just be stiff.

underneath the mirror is an Allen head bolt that clamps onto the ball of the mirror arm. This may come undone to allow easy movement.do not lube the mirror ball as your mirrors will move in the wind

What on earth is a "Wind Mirror" does it reflect the local breezes as they pass by?

as per @Hicap phill , + the ball/ball clamp and Allen screw rust up tight - WD40's no use as penetration fluid, use PlusGas and soak for a few days. Then loosen the Allen screw and rotate door mirror in all directions to remove crud/rust, clean up and use spray grease into ball/clamp/thread area. Then reassemble, position door mirror and tighten Allen screw.