Size of tracked plane

Hi guys, I’m trying to create an anchor on a tracked plane if it matches a desired size. Centering it on that plane.

Tracked plane Extent is where I believe I should start digging around, but I was curious if anyone has done something similar in the past and had some mental or actual code tips.

As I will have a desired size for an actual physical plane (think table) I’m trying to understand how I should relate that to the object (anchor) being positioned Nd it’s size, since I’d like to have it scaled accordingly. To ensure consistency I could have a ‘starting’ position to avoid scaling issues if that would help.

Thanks!