I just hexed him like any l4d2 model. Ofc into whatever hex editor, you gotta change IDST1 to IDST0 to make it work properly in sfm. Then copy the dx90.vtx file twice, and renaming both copies "dx80.vtx" and "sw.vtx" on their extensions. Welp at least that's what I did.
But since you're the one who did it, and I suppose you have the .qc's to compile them, I suggest you to compile them using tf2's compiler or just sfm's compiler (both have bin folders on their paths), so you can assure full compatibility with sfm. (And probably gmod).