jmanyou can do whatever you wish on that hull since it is out of warranty. Adding setback exponentially adds stress to the transom. In addition, too much setback can cause low speed handling problems such as excessive porposing. Lastly, you might find that your throttle cable is too short to accomodate the extra setback. In my opinion I wouldnt do anything greater than 6″ on that hull since it is older as the rewards you would see would be minimal.
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