It is hard to say for sure if changing the weight will change your spin numbers or how much effect it would have on the spin. Decreasing the weight will make the shaft slightly stiffer and that could decrease the spin a little. Increasing the weight will make the shaft slightly more flexible and that could both raise the ball flight and increase the spin a little. It really depends on what factors are creating the high spin numbers? The only way you can know for sure how a weight change might work for you it to experiment with a different weight.