Cut parts from Objects > Blend ?

Hi Designers!

I've made this grid using the Object > Blend mode in illustrator.

But I want to cut some parts out of it.

As you can see in the image it selects more paths then it should (those in the black area need to be untouched, but it auto selects it anyways) I supppose this is because of the effect the 'Blend' has.

How can I cut away those grid lines while still having the (object > blend) effect.

Thanks!

Greets,

Stylow