Travel N then NE about 24 miles to the town of San Mateo. My map seems to indicate the town was on the highway. In fact, NM- 605 skirts San Mateo to the north. The pavement ends very soon thereafter. The following log begins at the point where the pavement ends.
Road sidehills up the mesa.
Stay on 239. Stay left on 239. Up to here the road was mostly gravel and in decent shape. After the gate, the road becomes noticeably worse. From here on in it's slow going.