I'm pretty sure you can't. I tried to look on the Federation's site, even if you choose a state with no "completed x years residency" requirement (eg: CT)
I went through as though I was registering to take it, and before they ask for your CC info there's some fine print that says they must verify you've received your medical degree, and if they can't, you forfeit the registration fee ($400?)
I would've taken it end of 4th year, I'm taking it next week instead, I don't think it's a big difference in hindsight. If you're going into Transitional year, Internal med, etc... take it at the end of intern year, that year's experience will help you. I'm in Peds, so I just wanted it over with!
