Swapping model but keeping original animation

[ChibiShedevil]

There's been several mods out that I've seen that swap the model out to another creature but still keep the original creatures animations. I've been trying to wrap my head around this and make it work in the CK but have not been able to accomplish this. Does anyone know how it's done? I've been trying to make a custom race and switching around the model information in the CK but that just changes the model while keeping the animations to the original creature.