Pruning Young Duncan Mango

ipmango starts with ...
Just got a grafted Duncan Mango tree. My goal is to grow and keep a relatively small fruiting tree with a height of at most 6 to 10 feet due to space limitations.

The tree currently has 3 main branches stemming from the center branch; 2 growing off to the sides and 1 going straight up. I've been reading online that it is advantageous to have lateral or horizontal branches for both fruiting and for keeping a smaller mango tree.

at this stage of the tree's development, would it be wise to prune away that straight center branch at the red line in an effort to keep a short mango tree? Is it likely that 3 or 4 new branches will grow from the pruned center branch? Would I be better off pruning each of the ends of those three branches instead so that 3 or 4 new branches will start growing from the ends of the three established branches?

I'm new to growing mango trees; any help or insight would be greatly appreciated.

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