Okay, I drove over there on my lunch at work just now. Best bet is accessing the top of Bluemont from Vangilder rd and leaving another car at the base of Bluemont to drive back to the car on Vangilder after you hit the bottom of Bluemont.
It rises up to around 1800' elevation, and the top of Bluemont is 2000'. Save a lot of vertical distance for the first climb. It's pretty short distance to the top from here. The topo map puts it at about a half mile, only gaining 200 feet if elevation. Low angle, and most of it is open fields.
There's another road a little further down Valgilder Rd. It's a dead end called Alpine Heights (which seems like it was developed when the ski area was going a bit more, a few nice mountain tyle homes in there) It might put you closer to the top of Bluemont, but it's denser woods and hard to see much, but there is a nice turn around area, and it's well off the beaten path so it might be better for a low key operation, but I don't see any issues with either location to be honest.