It's a really nice place to visit...my dad and I camped overnight there in June of '79 and were able to drive out on a dirt road that was inside the loop to almost all the way to the end. Allow yourself enough time if you do this and you'll likely be rewarded.

I also caught 3985 there about 20 years ago on a westbound trip sans diesel. There's a nice bowl that you can get to above on the uphill track and capture most of any train. I've heard it referred to as the amphitheater. A good mile or so west of the Loop. Hope this helps some.