These videos are from Chris Wenzel at Truly Tropical farm in Delray Beach, FL.
There are many videos available on her channel, and are worth watching.
Part 2: Begin the grafting process to turn the Valencia Pride into an Ice Cream.
Chris does not mention it, but note that the graft wood she cuts has had the end leaves removed ahead of time to force the buds to begin to swell.
Part 3: Starting to clean up the tree, removing the old Valencia Pride parts.
Here is Chris with Walter Zill, top working Pickering onto an older mango tree.
Note that Mr. Zill is making a cut that leaves the cambium (the tissue between the bark and wood where the sap flows) intact across the most of the face of the veneer cut on the tree. Because the cambium is only one or two cells thick, this takes a lot of skill and practice to not cut too deep or too shallow.