i have an 87 trans am with a digital dash and i just put in a 00 ls1 and a 6 speed , my gauges all light up and i have the tach , speedo temp sensor working . my odometer dosnt show up ,dose anyone know how to get it to work ,

 

Sounds like you did not connect the wire that provides the signal from the PCM to the odometer. I would start by looking around for someone here who has done a 4th gen dash swap. Otherwise go to ls1tech.com and look for someone who has installed autometer guages.