Yup. And IIRC, gluing a fan directly onto the CPU or something too. Or not using a fan at all. Or pouring water onto the board to cool it. Something retarded like that anyway.
On-topic, a mobo is held on by a maximum of about 8 screws. They're universally placed, so in theory once the drive and power leads are out, you should be able to lift it directly from one to the other.
That's the theory anyway. In reality you might need to remove a card or two. But everything these days is designed so that you can't plug it into the wrong place, or the wrong way round.
Rule of thumb with drives - red part should point towards the power input. Simple