I just want to provide some performance tips for those who may be adding a CB and don't want lots of problems.
I don't run power or encourage anyone else to, my own is Cobra75WX all in the mic CB unit using all surface mount technology and none adjustable but great for space constraints. I do know that factory modulation limiters keep the modulation down to about 60% to prevent bleed over into harmonic frequencies such as TV which is the 2nd harmonic of the Citizen band. On better models like the Cobra GTL & LTD Series these are adjustable by trimpots. If you have a scope to watch your clipping it's nice but cleaner input modulation is a big key too which is why the D104M6 is a good choice over stock mics. They can sound different depending on make and model of the radio and even the astatic mics themselves vary. The power mic level and radio mic gain settings all play a big part in sound just as final output power of the AM transmitter does. Many people tweak up the power on CB's which actually works against the modulation circuit and creates more distortion. By turning down the power more modulation can be injected into the final transmitter circuit and will sound less tinny and allow for more amplitude during modulation so a 4 watt CB set to 2 or 3 watts still puts out the same amount of power when modulated by design but sounds much better. My own CB is used only during off-road events and still seems to be the cheapest and easiest way to add communications to your my which also seems to be what most Jeepers are still using these days. Many CB's today do not have metal chassis with knobs mounted to the front chassis frame and wires to the main board, but use a front circuit board with knobs or buttons soldered to it, problem there is vibration destroys this design faster and also hard impacts to the knobs making repair near impossible.