I assume you are talking about the lower control arm pivot? It is a short shaft about 10 inches long.
If you are replacing the bushing with a poly bushing, the original outer sleeve of the rubber bushing should be left in place. Just remove the rubber bushing from it by either tearing it apart or burning it out. The new poly bushing will just slide in with a little lube. The shaft should slide in fairly easy also. In my case I got a new shaft made for poly bushings. There is a different taper on the shaft to compensate for the slight difference in the poly bushing over the rubber ones.
If you are using the original rubber bushings, I am not sure, but you may have to press them in as I have not done them. I can see with the fact they were so hard to get out, they are probably pressed in .