Wing mirror adjustment ?

Is it possible to tighten them up in situ ?

If so what head does the screw have inside the mirror itself, thats the one you can’t see and can hardly reach ?

I ask this as with my motorsport rear cover and two wobbley wing mirrors I have zero rear visability !!

It’s a good job that i’m fast enough to be infront of everyone…

its a cross-head but don’t know how you get a screwdriver into it ??

is this where its loose ?