Conjunction box? Is that a coordinating, subordinating, or correlative conjunction box? (conjunctions are a part of grammar, a conjunction box doesn't exist...)

Maybe you're talking about a resistor box? If that's not what you're talking about, I have no clue.

If you're using EG injectors (high impedance), you don't use the resistor box. Resistor boxes are for the earlier (low impedance) injectors. The black and yellow wires from the injectors get connected to ignition switched power.