I also have a 72 Greavette Sunflash IV and have done quite a bit of research on the boat. Most Sunflash models were plywood construction however, you could have a planked version if you ordered it as Greavette would custom build boats to customers specifications. List price of a standard 1973 Sunflash IV was $7,200.
The Montique nameplate appeared in 1974 as Greavette was looking for a way to increase revenue. Wooden boat sales were down and costs were significantly higher. Fiberglass boats had become much better in construction, were more affordable and here to stay. Essentially by upgrading expensive to produce wooden boats to a luxury boat status it was hoped that the increased revenue could keep the wooden boats viable.
The Montique was based on the Sunflash IV with a planked hull as standard along with carpeted floor, tilt steering wheel, power steering, convertable top with side curtains, Power trim/tilt, upgraded interior and full insturmentation. The angular squared-off modern looking windscreen was a 1972/73 Sunflash IV running change and not unique to the Montique.
By 1978 Greavette tried to lower costs by producing a Sunflash IV/Montique hull in fiberglass but still adorned with a mahogony deck. Known as just the "Runabout", six were produced but this did not solve the company's woes.
By 1978 Greavette stopped producing wooden boats altogether. After a couple of years repairing and refinishing work only (hoping for contract builds and not getting any orders), they closed their doors for good.
The last all wood boats produced by Greavette were the Executive Mark II (only six of these 22' beauties were built) and an undetermined number of Montique models.