I made some of the holes in the side of the case for the charging port, SD-card access and the USB/UTP ports.

(USB ports for transfering roms and UTP port for.... internet)

(SD-card slot on the left and charging slot on the right)

It looks a bit weird on the photo, but it's actually easy to plug a cable into the charging port. SD card is a little more tricky to get out, but it doesn't have to be replaced often anyways, i just need to be able to replace the SD card when something goes wrong.

Next thing to do is drill holes for the shoulder buttons, power switch and volume potmeter, i will update this post when i get it done.

(Here's a nice photo of the insides, don't judge me for the hot-glue mess)

EDIT : I made the hole for the power switch and mounted it to the case, i had to extend some wires to make it reach to the side of the case because there was no more room at the bottom.