This will be also interesting but i guess it will be a long process. The first graft will take few months to heal and then you graft the other on top of it and so on.
However, if i am remember correctly, skill cult has a grafting video in which he is talking about such graft for apples - to put a dwarfing inter stock/scion in between the actual root stock and desired scion - to perform all those (two) grafts at the same time. I think that could be successful in apple, but not sure if it will work with the jack fruit.
Anyway, but the whole creation over the years will look really interesting, especially if you even add cempedak scions in between.....