Steamboy,
Hmmm...I'm not sure about that. I have never seen a 2RL to know. On a hopper, as long as it couples and the wheel flanges stay on the track, I wouldn't think it matters. The coupler sure looks like a 3-rail one and not a Kadee size, though I am told you can couple Kadees to 3-rail oversized couplers. Please share with us when you receive the hopper.
Myles,
You are so right about the delicate details. I do not have any of their engines, but I can imagine working on one care must be given.