How can you visually tell what balance a flywheel is? what years if any did they use them in mustangs? I have a flywheel that I put in an 88, and it ruined my main bearings from insane vibration, put a different flywheel in it (known 1990) and it was not only different looking, but of course the vibration went away. My buddy needs a 28oz flywheel, and I would guess that the one I took out was, but I need to know for sure. There isn't any local place that can check the balance or anything like that. Any and all help would be appreciated.