How do I remove deadzones from the edge of the trackpad?

I'm using this setup on my ThinkPad X230 with macOS Big Sur. Everything is working perfectly and I'm now ironing out the little kinks.

I've already changed FingerZ in SSDT-KBD.dsl from the default 47 to 30 and recompiled to increase the trackpad sensitivity. Now the tracking and gestures work perfectly.

However there seems to be a big deadzone around all of the already tiny trackpad on this laptop which I'd like to remove. Which value is responsible for this deadzone and what do I need to change it to to remove it?

Thanks