There are five pair of NG freight arch-bar trucks remaining at the EBT. Here are the only two sets still under thier respective hoppers:
[www.spikesys.com]
[www.spikesys.com]
The AB trucks you saw in the yard are now under the three ex-Cedar Point/ex-D&RGW cars. Their Andrews trucks set in the same spot for a while then were sold to the Friends of the C&TS in 2000.
Additionally, #12's and #14's tenders ride on Arch-Bars, but those would have come from Baldwin I assume. Also there are two cars with standard gauge AB trucks.
I have closeups of some of the ones now under the circus cars, but have never really analyzed them. The two from the side-discharge hoppers can be recognized by the spreader wing bracket attached to it.