No idea what they mean by second hole... weird.
It just replaces your current hitch pin.
Here's a great description of how it works:
http://www.letsgoaero.com/ProductDetail.asp?Pid=14
If you would like, I could send you mine for fitting purposes before you buy Sue.
I don't need it for a few more weeks.
Just pay shipping... Let me know.
---JIM---