Well, having sold licenses for a few years, here are the real rules. Many don't follow them, but be prepared for the guy behind the counter to follow them. You can get a license with your drivers license IF you are verified in the license system. If you are not, then you must present your hunter's safety card (not an old license) or they cannot sell you a license. To get verified, you have to follow the previously posted instructions. Getting your card verified also relinquishes you from having to have the card on you while hunting in CO. Yes, you are supposed to have it on you when hunting too.
If this is your first license, you better have your social security number also. It's required for everyone over 12 years old. Once entered into the system, it doesn't need it again, but you MUST give your SSN the first time. It's federal and state law.