Remove that crank shaft balancer belt pulley for good.
 

If you would like to remove that crank shaft balancer belt pulley, you can use Mitsu part# MD128107 in it's place. Is this really needed, NO. But I hated to see that heavy ass balancer belt pulley go back on only to be used as a spacer. When it comes to rotating mass, I believe every little bit helps. There is a big weight difference when using this spacer. This part number is a spacer that is used on the 1.6L engines that did not have a ballancer shafts/belts. Worked fine on my engine. Be sure to leave the thin shim between it and the timing belt sprocket on. Cost well under $10.

I was looking at that with my friend when we put my motor back together and thought it'd be a pretty slick idea. We were going to have his dad machine a spacer for us, but due to time and wanting to get the thing running again we deemed it to be not all that necessary.