Doesn't hurt to ask. I saw this Eastern Idaho GP35 sitting inside this industry, all fence in with lots of no trespassing signs. It was nicely positioned with the sun, with all it's lights on. I really want to get a shot of him, after contemplating for a bit, and seeing a sign that said that all visitors must sign in. I drove in to the office and asked if I could take some pictures of the locomotive. They guy said that would be fine, his only concern was that I didn't climb on it. I assured him that wasn't my intention. Sure glad I asked.
