As it's time to build the board, it may seem difficult to solder the microcontroller, which is a 32 pin QFP device. Actually it's not that hard, and it only requires a thin solder tip (1 mm). This is how the uC looks like one it is solded to the PCB.

The PCB almost completely populated:

It has two holes so you can screw the PCB to the Spectrum casing. One of them matches a mouting hole present in the Spectrum+ casing, that is not in use. The other one is not really a hole. It fits a screw present in the Spectrum+, near the loudspeaker. Simply raise that screw and use it to prevent the PCB from moving inwards when you push it while you plug-in the PS/2 keyboard.

Detail showing one of the mounting screws, power LED, JTAG connector, and the three pins of SV1 connector (from top to bottom: +5V, RESET, GND)

Detail showing the screw near the loudspeaker, which has been raised a little to fit the adapter PCB and prevent it to move.

Once it's mounted at the right side of the case:

The 8 pin header at the side of the loudspeaker is tilted slightly upwards, so the connector with the 8 wires from the Spectrum doesn't clash with the speaker.

The other end of the column and half-row cables is a piece of strip pin.

So you can "plug" the strip on the correspoding keyboard connector at the Spectrum side.

Using SV1 pins, we take power and ground to the adapter. At the right side we'll make a hole to reach the PS/2 connector from the outside.

It was easy to make the hole for the PS/2 connector, as the Spectrum+ case has a circle serigraphied at the same distance the hole has to be opened.

The hole for the PS/2 connector is wider than the connector itself because some PS/2 jacks have a wider handle.

Once it's programmed, the JTAG is of not use. We can freely close the Spectrum case and forget forever about the keyboard. Here you have it, with a wireless keyboard from Labtec.

For the next snapshot, these keys were typed at the wireless keyboard in sequence: 1 2 3 4 5 6 7 8 9 0 Q W E R T Y U I O P A S D F G H J K L Z X C V B N M , . - following the number keys (at the top of the keyboard) with shift pressed: ! " · (giving #) $ % & / ( ) = ? ¿ (giving !). This example comes from a spanish keyboard.