Mike, there are smarter Lefever mechanics than me out there, but, I have found that making a round headed "banger" to break the rust loose goes a long way toward making the spanner effective. I refer to my "banger" as "The Lefever Tool". I've only ever bought one loose Lefever in 65 years of collecting, so I don't need a spanner. If I ever need one, I'll call you.