It should just drop right in. I'm no expert with motor swaps, but I've done my share. I'm not too sure about the wiring harnesses, if they're interchangable or if you'll need a conversion. As far as mounts go, it shouldn't be a problem. You'll need to either get a Bseries throttle cable or modify yours. I'm not sure if the motors from HMO come with shift linkages and/or axles, but you'll need them.
It's definitely one of the easiest swaps out there.