imac mid2010, SSD added, what for bootcamp now ?

Yesterday i have added a SSD to my imac mid2010.

I used the second SATA channel free, saving so the supedrive that is inside the Imac.

With Carbon i will migrate the OSX (except some folder of my user) to the SSD.

Then i would to do a bootcamp partition on the SSD, to be fast with Windows.

Now i have bootcamp in the old HD, and it's a 32bit Windows7.

But because i have 8GB of RAM, i would like to install the 64bit version.

What i need to do exactly ?

I know i could migrate the bootcamp partition with Winclone, but id like to have the 64bit version.

So, which are the correct steps to do this ?

Thank you