Gauge Bezal
other thing you can do is send it out to a cluster repair shop, i believe they have the bench setup so they can put the needles on accurately such as supplying the cluster a speed signal of 55 mph then pressing the needle on pointing at 55. google gm cluster repair.
other thing you might try is just power the cluster with key on but engine not running and set all needles to point to zero. in my case that didn't work that great so i used my scanner.


