So, I bought a used iMac, and want to migrate to the new one using my Time Machine backup. Problem is, I go to Migration Assistant, and it asks for the admin password, which I don't have, and the place I bought it from is closed, of course. I had Lion on my old iMac, and I imagine my Time Machine backup is in Lion, but the iMac I bought has Snow Leopard. What do I do to migrate?