Who knew that Cow Creek has a West Fork? Well it does, and there's a road up it, and it's paved and maintained-ish. Signage at Cow Ck. says there used to be a little town there. RR line makes that plausible, and contemporary ORMC signage along stretches of the road are also explanatory, in their way.
Also according to signage, you can ride your bike all the way to Powers, Oregon on this road. I drove, at least this far. It was mellow today, but there is traffic, and from the looks of things active logging round about, so please stay aware. You're looking for a plastic ammo can, with some frankly uninspired starter shwag, but maybe you treasureheads can wrangle that.
What else do you need to know? Signage near GZ indicates a Coos-Douglas "district" division line, but I decided that was less interesting than where the road will take you. I spent a long time letting the Garmin settle into stable numbers, but still. Ah, wilderness. Therefore, in deference to all the effort you put into getting up here, the hint is a giveaway, so only look at it if you want that. Also in deference to the not-scary road into the half-clearcut wilderness, the D/T ratings reflect the whole journey, not just the GZ experience. You're welcome! :-)
Also, as always and ever, BYOP.