You should probably post this question at maestronet where there are more makers/luthiers about. I find it difficult to imagine that this is the best option, unless there is something more to it. If the neck is too long, it is easier to shorten it and fix the angles than to make and graft a new neck and still have to get the angles all right. These pictures do not adequately illustrate the problem, as it is a matter of measurements that are absolute more than visual generalizations. Good luck! A reset neck makes a world of difference.