I'm super into shimpaku junipers so I appreciate the link. I'd encourage you to go slowly and keep your tools sharp and clean. You don't have to define the perimeter of your final outcome with the razor. I will just cut out a thin sliver down to the hardwood to start off.
Anyone wrap the new Shari with long fiber sphagnum moss to keep it from desiccation? I think this is particularly important on smaller trees