Typically you'll want to swap to the rig of the target game when doing these sorts of ports. Additionally, I had to adjust the neckline verts, as they didn't match the K1 position, and I also added some plugs to the head mesh behind the dangly mesh hair piece, as that was causing all sort of visible gap issues (backface culling) that K1 seems particularly susceptible to.
Speaking of dangly meshes, they are currently broken in the latest beta version of MDLEdit, requiring compiling with MDLOps instead. May not be an issue if you are still on an older version though.