Ed,
I spline my butt sections the same way I do the tip: That is to find a hard, flat surface, hold the blank section at 45 degrees and apply pressure to the middle of the blank. In most cases, the rod will automatically slip to its splined position (the outside of the curve is the spline). If the rod seems to like 2 different positions, get someont to try to rotate the rod in both positions. The position in which the rod is most difficult to rotate is its strongest spline.
Swamp