http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0119.htm

There is almost a clear description and photos in the Shop Manual - this might be more useful to those with the mechanisms in-place.

However, there is only one way it can be installed, once you figure out which part goes where. The orientation of the top and bottom fittings that the threaded rods go through - you might have to try "both ways".