Looks like nobody else will guide you through this, because it's a little complicate.
You can install the 64bit on the SSD and will end up with a dual boot scenario. The bad part though is that the boot loader will be the one on the HDD, so can not format the old 32bit later. Better to start with the HDD disconnected and get a full install on the SSD. Tricky part: what do you need to prove the upgrade? I've never done it this way, but for a xp to 7 upgrade a xp CD does the job.