Nothing really special about how to print this.
Except from the fact that I'd recommend leaving cooling off. This is to prevent one side from cooling faster than the other, creating internal stresses when the arches are rejoined, which can lead to cracks, as it did for me... twice...

I don't think tolerances particularly matter.

I have attached .stl, stp, and fusion files so that you can more easily adjust to fit your laptop.

Trying to get the charger to allign was a bit of a struggle for me. I'd strongly recommend just taking a photo of your laptop's ports, uploading it to fusion, scaling it correctly, and then sketching around that. It's so much easier and wish I'd just thought of doing it that way originally.

The existing laptop channel width is 25mm and length 235mm.

It's height is to allow you to plug in HDMI cables and USB's from the bottom.