This self-portrait of the Merlin II prototype shows some modifications made in 1987. The original prototype was shown in the National Computer Fair in Rio de Janeiro in mid 1986 ( you can take a quick peek inside this prototype ).
The modifications consisted of the substitution of the Ethernet interface by a subset of the IBM PC's bus. This allowed the use of standard floppy and hard disk controllers, as shown.
This was the only prototype in the early history of Merlin that had a non-trivial amount of software developed for it.