A small board at the left of the Back phooto contains the control picaxe and a 74HC595 latched shift register. This only requires three output pins. An input pin measures the output of the pot wiper.
The six PnP transistors for the top row LEDs are on the upper board in the Back photo. The 110 green LEDs require the TO-5 transistors on the right. These are re-cycled germanium transistors. The board also contains the two decoder ICs and a high-current driver for the TO-5 transistors base current,
These are on a board under the row driver. You don't want to see it! Note the re-cycled germanium diodes which significantly increase the MOSFET gate drive voltage.