Best way to upgrade retail boxed version go build 1970?

I have a Core 2 Duo MacBook Pro on order and I'll be installing Parellels on it to run Windows XP. I have a retail boxed copy of Parallels and I want to seemlessly and painlessly upgrade it to 1970 when I install Parallels. What is the best way to do this?

My thinking is this:
1. Installed boxed copy to get Parallels license into OS X.
2. Download and install 1970

 

Just download and install 1970, don't bother with the boxed version. It will ask for your license key the first time you run it.

 

I assume that the license key is somewhere on the retail box or on the CD case, correct? I don't have my Parallels box in front of me at the moment so I cannot check.

 

Better way to download and install 1970. And enter license key from the box when prompted.

 

Found the license key on the CD sleeve inside my retail box. I'll download 1970 and install clean using that version. Thanks for the help!