A couple things to keep in mind when considering topwrapping:
- the TP is adjustable for a reason, slammed right down can increase sustain but lose some of the overtones. Many guys look for a sweet spot for overtones, close to the same break angle as over the nut.
- if you have a low neck set angle the top wrap might not work - the strings will be crossing the TP too high.
Here's a pic of the wrap on my Custom. The topwrap gives me about the same sweet spot with the benefits of a slammed TP,