Z bar question

I have 2 z bars for a 69 b body and one has an extra hole that the other doesn't. I'm hopefully attaching a picture of the one with the extra hole near the top, not the top one. Any ideas?? I'm clueless, not that that's unusual.

Some of the Mopar Z bars had holes in them for the return springs, some of them didn't I would use the one that works out the best