The Eterna was unique because of its mohair (burgundy) interior, bought to match their '63 Crown Royale Limousine combination*, which they still have. Other unusual features of this car include power windows--not available as a factory option until 1975--and a piped oxygen system. Other options on this car were an AM/FM radio, 176-D beacon, dual 250 spotlights, and a PA-20 siren.
*The window inserts seen in the photo above were from this car. Maury couldn't find the originals when I was there for the photo shoot.