Frankly, these instructions suck. There is a road that goes along the north side of the canyon for a while, but ends up on the south side at a dead end. You can't get near the Devil's Slide area because of private property/roads. We did find some ripple rock on the south side of the freeway, but were no where near the GPS coordinates listed at the xmission site above, which once again were inaccessible as far as we could tell.