You will need to create a second Adobe account to us both CC and stand alone versions.
Use the new ID for your stand-alone products.
Mohit that link is the one I used and will still use your CC subscription if you login with an account that has a subscription on it. Right now it appears all the installers are the same and your account login is the key to how it turns itself into LR 6 or LR CC
99jon, I found a different workaround that is a variation of what you recommend. Since I had purchased my standalone a while back and there is no easy option to transfer licenses between accounts, I was able to do this:
1) Create account for my wife with no licenses at all on it.
2) Install LR and when required to login, choose wife's account. The application will say there is no subscription and would you like to go into Trial mode. There is no option to enter serial number at this point, accept the trial mode.
3) Close LR and re-open LR.
4) Now there is an option to "buy" or something like that. When you choose that option, you can choose to enter serial number. The serial number doesn't have to be on the same account, it gets accepted and works fine.