Yep, same thing on my '65 C20. You'll probably just have to lube up that speedo cable. I was able to reach my hand behind the cluster and unscrew it, didn't have to pull the whole cluster out. If you do have to pull it, it's pretty dern easy and straightforward. Just poke your head under the dash and stare for a minute. If you've got gauges, I think it's best to separate the oil/fuel from back of cluster (held on with small sheet screws) before pulling it out. That is if your oil gauge is still hooked up with the original hard line. Good Luck.
