Recruit a Friend with existing trial account

I have a fully upgraded account (WoW1) and I want to RaF my WoW2 account. It is only a trial and have levelled 3 or 4 level 20s on it, but has only ever been a trial account, but it is over 2 years old. My question is, will RaFing my more-than-2-year-old trial account actually link the account, or do I have to delete the trial and make a new one to make it eligible? Thanks in advance :D