How are trucks, and couplers attached?

[gburgrailfan]

I have been looking around the internet trying to find some pictures of the bottom of rail cars. I have found one halfway decent image of a boxcar on it's side, but the trucks are gone. Ok this one is usable, kind of, it was taken so far away no real detail is visible.
Here is what I am doing, I am making some railroad, buildings, cars bridges etc. using Google SketchUp. The amount of data available online is surprisingly limited. Anybody here have a link to the ultimate resource, for railroad stuff?

[Pat]

http://techinfo.wabtec.com/DataFiles...ts/TP-2009.pdf