Some are content to leave the edges of the split fairly straight with only a small corner break. I'm not a huge fan of that look and prefer to machine a sizeable radius on either side of the split. Using a 7/16" radius cutting tool, carefully blend to face and inside surface of the rocker box.
Christian, Gearhead, Conservative, Republican, in that order. If you view my blog you will likely see pics, text, and video relating to family, motorcycles, religion, friends, art, politics, or anything else that sparks my interest.