We discovered that Skyline Drive closes at 5pm, and everyone is expected to be off [or at least heading to an exit] the Drive due to rampant deer hunting around the Park. However, the rangers want visitors to take sunset pictures, so we were OK.
Unfortunately, we didn't gauge our time and locations well. In hindsight, Pass Mountain overlook would have a great place to observe--but we kept going. Around Jeremy's Run Overlook, the sun was getting low, but the sun was dropping behind a mountain at the end of the Overlook. So, we continued on towards Gooney River Overlook--our final place to take pictures. After Jeremy's Run, we found the not yet set as we descended to Gooney River.
Finally, I experimented with the black and white settings for several locations--and I like the effects,
Pass Mountain Overlook, looking west to New Market Gap (left of center)