I got the new links, and there is no way that the current welded 'ball' will fit into these. I'll have to drill out the end of the bar and then bolt the link to bar. Any idea how large the hole in the bar should be -- the same size as the inner diameter of the 'sleeve' in the link? Or should it be large enough so that the sleeve (which sticks out about 1/8") can fit inside the hole?

Also what size bolt should I use? Is this a dealer item?