Factory radio removal

When I took the factory stereo out of my 2001 2500HD, the speedometer, tachometer, electronic transmission display and odometer, fuel guage and the message center all went dead. I took it out so that I could put in an adapter that would give me two RCA inputs through the auxilary. The converter hasn’t arrived yet so I haven’t put the stereo back in (partly because I can’t make the 9-pin connection reach far enough to plug it into the head unit before I slide it back in), but shouldn’t the stereo’s removal not affect those guages. I know it has something to do with the class 2 databus, but I haven’t been able to find this problem on any forums.