Na Dai sugar apple size?

[achetadomestica]

I have a small area on the South side of my house I was going to plant Na Dai sugar apple trees. Exactly how big will these trees get?
I have 4 trees that are one year old from plugs that are already 7-8' tall. My area is  6' x 17'. My question is could I hedge them and plant a tree every 5' and plant 3 trees or should I plant 2 trees? If anyone has a decent picture of an adult tree I would appreciate seeing the actual
adult tree?
THANKS
Mike