BOM and ballons in a big multi-level assembly

I have a big assembly (thousands of parts) structured on about 10 levels of sub-assemblies.

I want to make a drawing to help identifying some big sub-assemblies during montage.

So I have to insert balloons in the general (main) drawing, and this balloons have to be linked to different level sub-assemblies.

Is there a way in SW to specify how deep an indented BOM may go? In other words, can I make an indented BOM with only 4 (let's say) levels of indentation?

And another question: if I manually insert a balloon in the assembly, it will point to the part. Is it a way to select the assembly which includes the part?

SolidworksBill Of Materials