It is well known that the façade of the 80-key Mortier dance organ in the former Ghysels collection (now owned by the Flemish government - see p.51 in the book 'The Mortier Story') was assembled from parts of various façades (see e.g. this page on the website).
Thanks to research by Andrew E. Barrett it appears that the organ was originally built with a much larger façade for organ renter Corneille Helaerts:
Photo: collection J.Ghysels-Picalausa
The organ was almost certainly sold to dance hall "In het Konijntje" in Ostend (there are plent of indications that many organs from the Brussels region were sold second hand to dance halls at the Belgian coast); the instrument was rebuilt, though: e.g. the cello pipes were moved to the lower side cases and two of the decorative panels were moved on top of the side cases:
Photo: collection www.vliz.be
Later the organ ended up with organ builder Stelleman in the Netherlands. When Jef Ghysels bought the organ for his collection, the missing façade parts had already been replaced by parts of a.o. another Mortier and a Koenigsberg dance organ:
Photo: Björn Isebaert
However, some of the original façade panels were acquired by a Belgian collector and these seem to confirm that the organ of Corneille Helaerts and the one formerly owned by Jef Ghysels are one and the same instruent:
