I realized that the palette selector for the RGB mod is supposed to be a SPDT "On-Off-On" switch. Unfortunately, I cannot find a switch that is the correct height from the PCB (6 mm) and only 15 mm wide. Almost all miniature slide switches these days are 2.5 mm tall.
I want to try and use parts that are readily available from Mouser, so I chose a DP3T switch. (Dual pole was actually easier to get than SP3T in the size I needed)
Because of the width of the switch, this means you will have to widen the slot on the back by about 5 mm if you plan to use it. You have to modify the case anyways if you want to use RGB, so it shouldn't make much of a difference.
Of course, you don't have to put the switch in at all if you aren't going to use RGB.