I guess I should've described this in the thread instead of the feedback system, because my quick description probably wasn't clear- at the point, you can stand on the shelf props on the carts and look out through the cracks at the too below the curtain prop (or whatever you would call the draping roof of the cart). If I was a better Sniper, I could've done some serious damage with just my head exposed.
Edit: The cart furthest away from the incoming team (so on that team's opposite side) seemed to have the best vantage point.