Once you install the plate, it’s difficult to replace the diodes. For this reason, I recommend installing them on the bottom side of the PCB (the side where the switches won’t be). If you plan to use Choc switches, the diodes need to be on the bottom side, otherwise the plate won’t fit.
Start by bending the diodes. You can use a special tool for it, called a lead bender. If you don’t have a lead bender, you may choose to use the switch plate for it, or a pair of pliers.
Starting with revision 2.0, the right side also has diode D26. Install this diode too, unless you are using a nice!nano controller.
Insert the diodes into the printed circuit board, having the diodes on the bottom side. The places where you’ll need to insert diodes are marked with D1 to D25. Most of these footprints will be aligned vertically next to each switch. Pay attention to the orientation of the diodes: they will only work when they’re oriented correctly. The black line on the diode always faces the square pad.
Using Kailh Low Profile Choc Switches. Because of the lower profile of the switches, soldering the components to the bottom of the PCB is required. If you don't, there won't be enough room for the switch plate.
After you’ve inserted the diodes, you may bend the legs outward to keep them in place while soldering.
Which side to solder: Usually, it's easiest to solder the side where the legs are sticking up. The exception to this is when using Choc switches. Since you want the plate to sit as flush as possible later on, you should solder the legs from the same side as you placed the diodes. This makes it easier to cut the diode legs flush. With MX switches, this isn't as important since there will be plenty of space between the plate and the PCB, so you can solder it from the side of the legs to make your work easier.
After soldering the diodes, clip off the diode legs from the top side of the PCB. If you’re planning on socketing the microcontrollers, you may want to save the diode legs to help you socket them later.