Hey guys I have been trying to throw the rear end of the car together before I move in a few weeks. I am swapping the rear control arm bushings from the stock ones to a set of used aftermarket ones. I had to burn the old ones out but now they are free and its time to put the new ones in. I had to try my very best and I was able to get one side in but it was way harder then expected and doesn't sit right in the arm so here is my Q
There seems to be a thin sleeve inside the arm that is in two pieces is that a part of the arm or the old stack bushings? Did some googling and came up with a few pic but I didn't seem them in arms with aftermarket bushings.
Here is what im talking about.

This photo shows the gap between the two

Here is the overlap on the outside that I have not seen in photos online
