Hi Dave,Dave wrote:You can clean out the holes and put in a socket strip to create a riser for a memory card or any other card within the power limits and space limits of the QL.
Adding the mouse option is all TTL logic plus one programmed PAL as I recall. It also had a different EPROM.
The Mouse changes look straight forward and probably a standard ram expansion board could fitted or another QL Expansion connector.
Just out of interest, do you have a schematic for the ram board?