speedometer/odometer do not work - '87 civic

Any suggestions? It's a decent car that I'm tryin to fix up one step at a time. It runs great, but the dang speedometer and odometer don't work. I found the speedometer cable, and was wondering if the odometer reading is governed by the speedometer output. I don't want to waste time/money replacing that cable if the two are in no way related.

Thanks a lot in advance - if you have any microbiology questions, I'll do my best to help! :P

well, it is possible that on your 3G the guage cluster has crapped out on you, i honestly couldnt tell you, however someplace to look is www.redpepperracing.com where they specialize on 3G Civics, such as ours.