Grohe Thermostatic

We just built a new house and put a Grohe system in our master shower.

Being true Americans I HATE not being able to take a hot shower. I
want to spend more money on fuel. I want to waste resources. However
the Grohe system limits my shower temperature to only 110 degrees.

I took the face plate off and have looked at the website - but I
don't know how to - or just can't figure out how to recalibrate
the max temperature.

Anybody have an idea?

The valve assembly looks like it has four hex "slots". These are
rather large and I don't know their function. I don't want to
start messing with things unless I know it will work.

Thanks