Try and solder the back of the circuit board first. That's more than likely the problem. Mine would randomly go on and off at times. Sometimes it would stay on for days, other days nothing. Sometimes its would be constantly on and off and the cluster was basically a needle free for all. Try tapping it a lot when your driving and see what happens, if they move at all, then it's the circuitry.
I spent countless hours dealing with my intermittent cluster failures. Even did the soldering technique which had no effect. After two years with no insturments at all, and giving it to my son to drive, I coughed up 48 dollars on ebay and got a new circuit board. Best 50 bucks I've spent in a while. Two months out and it is flawless.