balancer
Both balancers are internally balanced, but you need to use the one that TDC lines up with the timing cover marks. Some have TDC at the 12 o'clock position and the cover has the tab welded on, while some are closer to the 2 o'clock position and have the bolt on tab.
It would be best to have the crank balanced to the heavier rods and pistons, but they do have the same stroke and are both internally balanced.
Bill