This is a rough idea for a display panel using a servo to show the output of the ALU. Input is being made with IO's front panel data switches.

This is Uglytech at its best :-)

This is a cleaned up version. Not as ugly but still Uglytech.

The ALU feeds its output to the 4 to 16 line decoder on the left. The output from the decoder goes to a resistor bank on the lower right and then to the astable multi-vibrator upper right that then sends its output to the servo.

This is how my Winscope sees the servo signal. Not bad for a simple two transistor astable :-)