You can insert on end in C1, C2, or C3 and the other in C5.
From the article:
I simply insert the resistor 75 Ω is the ideal spec in the DVI output port to make contact between C1-C5 (analog red - analog ground), or C2-C5 (green - ground), or C3-C5 (blue - ground).
It's the same thing as using a dummy plug, except that you can remove the dummy plug whenever.