SACHS fork thread

[jra_enduro]

Hi
I have tried to search both the forum and the net but did not find much therefor im trying to start this thread.
I have 2 new GG 300 with the sachs fork on and we have figured out after only a hour of riding that the fork is to soft for Swedish riding and Swedish vikings that weights around 90kg
So what im looking for first of all is new harder springs (5,6 should work fine i guess) So can anyone tell what springs that fits this fork?

Then it comes to oil. What viscosity should i run? Normaly on the bikes i have ride before we have used ?hlins road and track oil 5W and that have worked flawless in both MZ and KYB.
And what oillevel should we have, around 110mm? We ride rocky and woody trails mostly here.

Then we come to the valves have anyone tried to revalve and how did a good working stack(is it correct in english?) look like

So can anyone help me out here?