When should I cut back the rootstock of a grafted sugar maple? on Saturday I grafted a a piece of soft budwood from a sugar maple in my great aunts yard onto a sugar maple sapling I baught from amazon to use as rootstalk. I used the veneer graft method but left the terminal shout on the top of the rootstalking growing hoping to feed the graft as it heals. Should I leave it growing or cut it back to feed energy into the scion?

The reason Im grafting this is because my great aunt the one the tree belonged to passed away a few years ago and Im trying to grow this in her memory. Does anybody have any tips on caring for this graft? Should I keep the rootstalk growing until the graft heals or snip the terminal growth tip on? Thanks.