I have this model, but not the written instructions.
There is a single adjustment for the focus of the eyepiece. The eyepiece slides in the barrel, and there is a small screw on the eyepiece barrel which locks the eyepiece. In normal light hold the finder and look in the eyepiece, you will see a bright field and a crosswire, unlock the screw, move the eyepiece to obtain sharp focus of the crosswire, lock the screw.
For those wishing to take a little more care go outside and do the procedure with one eye at the eyepiece and the other eye open, relaxed and focused on a distant object, now make the crosswire focus adjustment. This method makes it easier to view the grain because the eyepiece is focused with the eye relaxed and focused at infinity.