Less than a lot and more than a little? I've never worried about it, it wasn't an interference issue. So probably at least a 1/2" or more.
I'll see if I can look at it tomorrow. Now that I've gone hydraulic I don't have a z-bar stuffed in there anymore so I may be able to check it without getting under the car. I have a Milodon road race pan, but the kick-outs are ahead of anywhere the #3 tube should be so I should have a relevant reference point to measure from.