Just bought a glasbed for my wanhao but when I put it on the bed becomes to high, so even if the springs is fully stretched the extruder will still make contact with the bed in some places.
Should i move the z-axis end stop to the higher position? (to the two holes right over the ones that they are now palced in?)
yes.
on my system there were 2 screw holes just above where the z-axis is currently screwed to.
Yes, adding glass does cause the bed to be too high. Print this: http://www.thingiverse.com/thing:928008
It allows you to move the z-axis endstop up, and also gives you a nice adjustable z-endstop.
I assume you also removed the BuildTak layer if your printer shipped with it? On mine I could not get the glass to stay in one place with the build tak on the bed - I tore off the buildtak (just be careful, it’s easy to bend the bed while doing this).
There are 2 additional holes for the z- axis end stop to be raised. Just be careful when unscrewing. be gentle with it. You don’t want to break the plastic on the end stops.