I always obey imperative commands, so we parked at the sign as told. Then after a slight detour to White Mountain, hiked the road to the summit. Easy walking on the road (don't try shortcutting the switchback- the road banks are awful).
Drove 4Runner up to about 9,400 feet at which point exposure forced me to park. Sign said "park here". Then walked road last 1.5 miles/900 ft to permanently manned lookout on top. Did in evening so it provided very nice views of surrounding ranges in a different light.