Do a fresh install on the SSD, it's a better idea. Since this is your first SSD - watch out, you won't want to go back to a HDD ever again!
Oh and a couple of things...
Before installing Windows on it, make sure "AHCI" is selected in the BIOS for your SATA ports. Then, install Windows and everything else. Windows has some features that you may not use but they are enabled by default and occupy a fair bit of space. One of them is Power Hibernation. If you don't use this, go to the Command Prompt (run as administrator) and type:
powercfg -h off
It won't confirm anything but you'll notice you have about 5GB extra free space on your SSD. Also, if you don't use System Restore, disable that too. Oh and since you have A LOT of RAM, you don't need a big page file. By default, Windows will create a massive one so set a fixed page file size of 512MB or so. Technically you can probably do with less but you want some safety leeway so you don't get some random crash because of virtual memory. 512MB works great for me and I have less RAM than you.
By doing all these things, you'll get about 11GB extra free space on your SSD. Good enough for a game or two!