In the store I was asked if I had a GMail account, I thought I did, but wasn't sure so I created a new one. Well it turns out that I DID have an existing gmail account and want to use that one (the email address is the same as my yahoo prefix and it would be an easier transition for everyone). How do I now link my Droid phone to my pre-existing gmail? Do I have to reset it to factory settings and then start fresh? Thanks in advance.