Don't forget to check the torque on the rocker shaft assembly mounting bolts before you adjust as well. It will make a difference.
I don't recall having to take the rocker assembly off to torque my head bolts either. IIRC, my socket was just the right hight to clear it, it's a Mac 3/4 thinwall semi-deep impact socket, and I was using a Snap-On torque wrench.
