[NTG-context] gtamac symbols and mkiv

I have been using symbols (such as "Fleuron") from the gtamacfonts in an annual publication. Trying to change to mkiv: what exactly should I do to install them? So far, my attempts were not successful. (Attempts meaning: copying the tt fonts and the type- and other files that seem to have anything to do with it into my minimal installation, reloading the fonts and remaking the formats). Thanks, Jörg