I'm glad you asked this question, because I have a related one (don't mean to hijack your thread).
I installed cleats on some new bike shoes I got on ebay (look type, I think). Anyway, it seems there is another bracket for a different type cleat on the bottom of the shoe, and it rattles around while I'm riding and walking. How do you stop that rattle? Glue? Or did I install my cleats wrong?

Here's a link to a thread about speedplay cleats:
http://www.bikesportmichigan.com/reviews/speed0.shtml

And a link to the type cleats that I have:
http://www.nashbar.com/tech/pdf_files/VENTOUXR.PDF

Not sure if this will help you or not, but the second link is about all the info that came with my pedals and cleats!