duddygoober,
So far, I think there could be at least four possible sway bars that have creeped into this discussion.
Used sway bars from a 47-55 AD truck (Jim Carter sells them).
1. 1947.5-1950/51
2. 1951-1955.5
A sway bar from an automobile (or later truck with a front swing-arm?):
3. Gord's link above to an earlier thread on this topic shows a posting of a non-AD sway bar - might be same vintage automobile?
An aftermarket sway bar
4. Jim Carter, HP154, SWAY BAR ASMBLY 47-55 1ST 1/2 TON, for example
My guess is that each of the four assemblies have a different installation configuration. Your call to Jim Carter should clarify this.
Tim