Lower ball joint help
 

I bought a standard front end rebuild for my '66 Catalina from PST. Everything was going fine until I tried to bolt the lower ball joints to the spindle. They will not go through the spindle to allow the nut to start. They are the correct part # and look like the old ones but I'm afraid to beat on them too much to drive them through. Is there a preferred method of doing this? I tried a socket over the hole and a jack underneath but I didn't get anywhere.