HUD - Get Actors in Selection Rectangle - Any way to improve on it ?

I have got a dragging, RTS style selection box working using the “Get actors in Selection Rectangle” but the results are really sloppy.
I can be almost half a centimetre away from a mesh and it will still recognise and grab it. I understand this is because the node is reading the mesh bounds ?
Is there a different, more precise way to do this ? Or a way to improve the node’s results ?

I’m trying something different but I need some help.
I found this formula and I thought to implement it in blueprint but i’m failing. Here is the formula:

(From: algorithm - Finding whether a point lies inside a rectangle or not - Stack Overflow)

and here is my blueprint interpretation:

What am I doing wrong ?

I managed on my own. Leaving this here for the people of the future (WARNING: i’m not a programmer):