On my 2002, there is one adjustment piece on each headlight. It appears to be a bolt with the last 1cm or so that is hex shaped.
As I started to turn it with an adjustable wrench, it began to strip. A tiny pair of pliers did the same. It must be made of aluminum. I didn't have a 4mm socket either, so I had to create a tool out of a 4mm hex bolt, and two 8mm nuts. Then I used an 8mm wrench to turn this tool. Socket wrench wouldn't fit with the 8mm socket, stepdown adapter, and the wrench itself.
Yours might be stiff too, so don't force it. Do it slowly, and make very very certain it's actually turning even if it feels like it... before it breaks. You'll need a flashlight, too.
My Volant intake box would have to come off in order to adjust the right side. Booo.
Left side is very accessible.