hifi engine

Pioneer SM-G205 Adjust???

I have a Pioneer Tube SM-G205, with two Output transformer. One Output transformer are to hot,
now I will adjust K1 and k2, I have only the chematic not the Service Manual. K1=VR5, k2=Vr6.
I think the Bias is not ok?? I have no Idea how Adjust it. Can someone help me???
Sorry for my bad English.