Absolutely correct, Pete. The short WD hangers are identical regardless of footrest type fitted. The sets available have usually been re-packaged in the 1950s and it's rare to receive a pair of hangers with the same finish (you'll need dull chrome).
The later rests do simply unscrew. They're too short to turn down as centre studs for the pedal type rests though.
As we discussed by mail (but I'll mention it here for the benefit of the forum), the pre-/early-war rubbers are 1/8" shorter and have a more rounded profile than those fitted post-war by Norton.