Agree with @72Duster440 , it's such a tight fit that it might not be necessary, but a thin film of RTV is good insurance against imperfections the bore may have developed over the years.
When you re-install the converter, take one last look at the impeller hub and make sure there aren't any scores or ridges. And be CAREFUL not to damage the new seal. If you slit the seal somehow during converter installation, you will find out, but it'll be after everything is put back together and the engine is running...
