eddiespaghetti - best to avoid Personal Messages and keep the discussion in the forum post. That way it might help others in a similar situation in future.
I'll answer you question here though. I realise wasn't 100% clear.
If I understand it, your final goal is to have a fresh Windows 10 build on your new SSD. Is that right?
If so, Windows has made it clear that if you want to do a fresh build of Windows 10 rather than an update, what you do is:
1) run the in-place update.
2) download the (correct-for-your-version) Win10 ISO and burn to DVD/bootable USB
3) perform the fresh install
Apparently in Step 1 Microsoft logs your hardware such that if you perform a fresh install on the same computer in future it will successfully activate you without a licence key.
If I've understood you correctly, what I'm suggesting you do is install your SSD into the laptop immediately prior to starting Step 3 above. That way you get the fresh Win10 install on your new SSD. See my post above about the potential for the activation process to fail because you have changed your hardware slightly between the updgarded Win10 and the fresh install. But at worst, a simple phone call to Microsoft (they'll give you the number when you try to activate) should get you up and running.
I think it's absolutely fine to try this as if you have activation issues on the fresh SSD build you can always put your HDD back in with the upgraded Win10 while you figure out what to try next.