Here is the backside of the signal after the rebuild. The gentlemen who did the sandblasting were so good that they managed to save the old rope type gaskets on the back door cover, since the rope gaskets were in great shape I did not want to disturb them. They blasted the whole unit all the way down to the clean cast iron! Both inside and out. I added the brass signal lock (old SP vintage) to give it the complete look. The only problem is that I know it was made by US&S, but I don't know what the "type" is. Someone said maybe a TP-5 ????