86 redbird

Today I went to a junkyard with a buddy of mine looking for some firebird parts when i stumbled across an old trans am that had the instrument cluster with the 8 grand tach. My TA has a stock 6 grand tach, and I was wondering 2 things. 1 will the cluster be worth anything after being in a junk yard? 2 Would the gages work with the different tach or would it still read like I had the 6 grand tach? I would really like to switch because I'm about to put a new engine in the car and I don't want to use an aftermarket tach.