I think I found my vibration problem

Bill, are you sure this engine even has a cast crank in it ?

Yes, the damper I pulled off of the engine was the one pictured in post # 46 at the top. The # on it was 3830482 I believe. I found the paperwork on the new balancer I bought from 440 source. Part # is 200-1128. I left the weight on when I put the balancer on. Now I need to know something here. Lets assume that this guy who put this engine together didn't balance the engine, which I can almost know for a fact he didn't, would this cause a vibration especially if he put say old rods or other pistons in it. Also, the weights for the converter came in today from PTC that Kenny told me to put on the converter. I think someone said they put them on and it works . What do I do. weld them on or leave them off.