How do I level this

[nikos1]

Im out of ideas, 4 times is too much. There are no true verticals in the whole picture to accurately level by. Ive tried leveling by the end of the unit but that still doesnt help, would it help to point out in the comments to screeners that the stop sign is in no way level.
Ignore the typo lol
First try
http://www.railpictures.net/viewreje...&key=642214445
Second
http://www.railpictures.net/viewreje...key=1167728856
third
http://www.railpictures.net/viewreje...key=1094253573
fourth
http://www.railpictures.net/viewreje...&key=890415591