Polyurethane bushing squeak
Poly and rubber bushings function very differently. In the rubber version, nothing spins, the movement of the UCA is just flex in the rubber. The poly is too stiff to flex like that, so, the bushing must spin. In the case of those bushings, the bushing is likely spinning on the inner metal sleeve. The only other possibility is that the whole bushing, including the metal sleeve, is spinning on the camber bolt. But a lot of times, like with the factory bushings, the inner sleeve will not spin on the bolt because it will be captured when you tighten the camber bolt.
To grease that style of upper bushing you need to pull the inner metal sleeve (that the bolt goes through) and grease the outside of the sleeve and the inside of the poly bushing (and a little on the camber bolt too, but that’s for any kind of bushing). Typically with that kind of bushing the poly is tight enough in the outer shell that it won’t spin there and therefore can’t easily be removed from the shell. But if it’s not tight in the outer shell (like it’s a slip fit) then you need grease between the bushing and the outer sleeve as well. It has to spin somewhere, it won’t flex.
Also, one of the reasons I don’t like kits. They should specifically list all the individual parts they sent you with the part # and manufacturer so you know what you have. Mystery meat is not a good thing.