Illustrator: automatically group each shape with the text inside it for a huge collection of retangles

I have a .dwg (AutoCad file) map full of fields (rectangles) that I'm manipulating with Illustrator. Each rectangle has a text inside it that indicates its number. The problem is that there is no association between the rectangle and its number and that's what I'm trying to do. Also the order or drawing is not the same, when I check the layers.

Is there a way with Illustrator that can group each rectangle to the text inside it and this for all the fields? It is possible manually, but impossible to do it for every single field: about 40.000 rectangles.

I guess the approach should have something to do with "closeness" since it's the only data that tells us the correspondence between a rectangle and its number.

Thank you in advance, any help would be much appreciated .