I think it might, yes. But I wouldn't recommend opening up the iMac. Pretty much any other Mac, sure, but not the iMac. Messy to take apart and put back together.
I recommend an enclosure for Thunderbolt instead. More expensive, but less hassle.
Put one in an external case or better still get an external SSD from OWC and connect it via Thunderbolt. It won't be as quick as the internal one, but it will work and you won't need to open up your machine. It will be fast enough for those of us using it in the real world though and not worried about bench marks and theoretical speeds.