When this thread started I was a little dissapointed because my vehicle had never been in Big Bend. Neither had I. I have been anxiously awaiting the day I could post my own "vehicle in Big Bend" picture. Well, I'm thrilled to finally be able to join the club.
Here is a picture of my new truck approaching the McKinney ranch site on Old Ore Road. As you can see, it is already pin striped which happend on one of the 2WD roads in BBRSP before I realized it. Since the first pin stripes were already out of the way, braving Old Ore in the new truck was an easy decision.
And this is a picture at the end of Indian Head road just outside of the park. Since you can see the park from the picture, hopefully this counts.
I'm working on a trip report which will hopefully arrive soon.