They are indeed poly bushings. Right now they fit tight enough that pivoting them up/down is almost a 2 handed job, but not difficult... definitely staying still unless moved by hand. I did end up having to pop the metal caps out of the bushings on the inner side of each arm and use the grinder to thin them out a bit, otherwise they simply would not slide into position on the car. Either bushing stack would fit into their respective position, but not both at the same time. Like the 2 legs were just a hair too close together.
I'm hoping to get #2 installed tonight and will see how it goes in comparison to #1.