Now I have the triggers in their places, 50 of them, and 25 of them wired to triggering line number 1:
You can see two lines of transistors in the lower section, and the lowest line of transistors wired to one lane:
They will be the "on" trigger, and line of transistors above that will be "off" line. Then there are three 4017's, which will select the led, and then by using triggers, the corresponding led will go on or off accordingly.
There will be a lot of wiring, and three meters of cable won't probably be enough.