Let me assure you that you can't screw this up! Trim that rootball and transplant.. You'll be fine I promise! One or two inches off the bottom and same on the sides and transplant.Plain ole ph'd water on one side of the pot. Gotta give it a chance to dry out some. Roots grow faster if they are somewhat dry. Maybe add some KLN rooting hormone.

That new growth your concerned about is gonna be explosive!

Ga.