Charles,
There really isn't much to debate, as the original ML-10 had a total production of only 3000 or so units, is obsolete, and there is hardly any reason to convert it to anything. A piece of pipe can be converted to a 12 ga. shotgun with less trouble, easier yet to a .22 rimfire. Not necessarily smart / good / safe . . . but aren't 100 year old cartridge guns non GCA, non 4473 arms? What is the issue?
One of my favorite muzzleloaders is the Encore, which of course is a form 4473 arm, with as easy a change to CF as can be hoped for.