I think that you've got the wrong upper as well. I've never seen an upper ball joint for these trucks that didn't bolt in. As for the lower one, those just press in and over the years, the hole in the a arm has a tendency to "wallow out" to the point that a new ball joint won't press into the hole with a snug fit. Try the new stock one, and if you can shove it into place with just your bare hands, then the hole is too big and you need to take it back and trade up to an oversized one.
In either case, when you're pressing the new one in, the easiest way that I've found is to raise the truck by the front cross member or frame, then when you have the new one started, come up from underneath it with a piece of wood on a floor jack. When you've got some tension on the floor jack (and you're sure that the ball joint is still sitting straight in the hole) encourage it into place by tapping down on the a-arm all around the joint with a hammer. Note; you have to do this before you install the grease zerk so as not to break it off
