My dad's 82 diesel Suburban had that AM/FM/CB in it. IIRC it had 2 antenna inputs and a splitter box under the dash, plus a special antenna to make it all work. After it stopped working right (can't remember if it lost CB or FM), we put in an aftermarket unit (high-tech! auto-reverse cassette with 5-band EQ) and couldn't get good radio reception until getting rid of the splitter box and putting in a standard antenna. Thinking back on it now, I wonder if the antenna/splitter was the only problem or if it was that the digit display for the CB stopped working.
