how to solder in a diode

Working with my wiring for ignition MSD. Was doing some reading and some recommend soldering in a diode it the 12v small red wire...



How do you put it in? Assuming one end of wire soldered in. And the other end of wire soldered to the other end of the diode. The one that came with my box looks similar to this. I learn well via You Tube but couldnt find a good video duplicating what i need.