Prepping for t-budding

My first attempt at t-budding will be soon and I have questions on prepping, the graft and the rootstock. The rootstock is B9-337 and is growing in the orchard as the scion died 2 years ago. One sprout is 6" away from the main plant, about 3’ tall, and I wish to bud that and then transplant it. Your wise commentary is desired.

Watch the video @applenut put together. It’s the best I’ve seen:


Here’s what it looks like with someone who does it for a living.

Fancy T-Budding