adrian - I called and asked - their reply was that they use similar instructions for all sizes - OK I buy that and they said that the 120 size does not come w/ a spinner b/c with larger engines most people (me too) want to use a metal spinner.
Even if I got the plastic, I'd use metal. I had a Vmar kit (piece of crap - all their products!)and the plastic spinner wobbled. I chucked it.
Best to use metal w/ an engine 60 or over.
tfacr