You're probably already aware of this, but there is a couple of great vantage points from the rolling hills/dirt area between Seneca Road and Forest Hills Dr., compass west of the mainline. This area provides excellent late afternoon light, with the Horseshoe Lake in the background. I've experienced late afternoon lighting that reflects hard off the ScotchLite lettering of locomotives- really neat!

Also, in the same area, there is a dirt road that ends perpendicular to the compass west side of the mainline just railroad west of the Frost XO (NOT the Natural Crossover- that's a little further west). Where it ends, there was at one time a nice ranch-type fenceline and a pasture with trees near the Frost XO signals. Great shots can be had here, as well. Google Maps shows part of it as Kemper Campbell Ranch Road.

I would like to have joined up, but that's a bit far away from me. Good luck, and I look forward to seeing your posts!