Is it possible to adjust head height on vj628?

[Racegrafix]

Just as title says, I know there is two white pieces with possibly a bolt going throught them, but those were so insanely tight they just stripped instantly. (correct snap on 6 point socket). I dont see that being possible, or how it could possibly do anything. So is there an actual way to do it? The manual is super vague and says loosen screw (no idea which) and go "up" to raise. Makes zero sense. DO you just use shims under head?

 

[chrisphilipps]

There is an orange lever on the left side of the carriage. When it is pointing down it is in the low head height, when it is pointing straight out it is in the high head height. The only other height adjustment is service related and it is only changed if the carriage isn't within spec.

Low Head Height:

High Head Height: