An adapter that will fit the original Melzi board footprint used in the Duplicator I3 and has mounting holes offset to mount a RAMPS 1.4 / Arduino Mega board if you feel the urge to upgrade your printer. The RAMPS board has to mount very close to the edge of the enclosure so I offset the board and put the power connectors and the USB towards the back where the power supply and harness wires would be.

Use at your own risk. I made a similar board for myself that adapts a RADDS board so the main footprint works and the mega footprint is correct. You can see from the renderings how it looks.