So after reading through all of these forums, looks like anything 00+ is interchangeable and anything 99- is exact fit only, Sunfires and Cavaliers have different sized IPC so they don't interchange cleanly. So what do I do when I have an apparently rare 1998 Cavalier z24 manual transmission cluster with digital odometer? I can't find one anywhere. Can I have it shipped off somewhere for repair? Can I possibly repair it myself? The biggest problem my cluster has is the digital odometer only works 1/4 of the time.
Thanks everyone,
Casey

A 99 should work in your car. They switched in late 98 to what was going into the 99s. If you can't find one of those, you may just have to have your cluster repaired. Search on ebay for "gauge repair service" or similar. I know there are a few places on there that do it. Even if you don't find a listing for your exact thing, I'm sure if you contact them, they can help you out.

Somewhere in the 98 or 99 timeframe the fuel level sending unit changed, resulting in a inoperable fuel gauge using an older cluster.

If the problem is the digits not working completely, intermittently or whatever, I found that on my cluster working the trip set/reset button repeatedly would gradually coax them back to life. Once I had them working reliably again, I adopted the practice of resetting the trip odometer whenever I fuel up so the switch gets used. It's been fine ever since. I tried opening up the cluster to see if I could reach the switch to clean the contacts, but my recollection is that I either couldn't get there or I was sure I'd break it if I tried. So, I left well enough alone. - Mark