Us commoners will probably never find out but it sure would be interesting to learn how these slime bags found out that brass was there in the first place, how to find,place and use the equipment to jack the trucks and remove the brasses as well. It takes time and allot of effort to perform this task. Or are they known to railroad preservation and restoration groups? Your average junkie isn't going to know that stuff is in there unless he is taught. For those of you that are working on restoration projects, forget about historical accuracy until you can have your equipment locked in a secure building. Paint all your copper and brass pieces black so they blend in with the rest of the project and the public won't know it's there. Having it all polished up for show and tell is a sure way for it to disappear. If they will try to take a steam whistle off of an operating steam locomotive, they'll take anything that isn't welded to it.
Bill