The ninty slots come straight from the original board, generally we just cut the board right around the part we're looking for to make sure we don't melt it.
If its ok to ask, i saw there on the cad model, the bottom left hole appears to be a barrel jack for power, the top right hole in the bottom peice is a USB since there is a USB mount, and the hole in the top left, is that the power switch? Is the top middle round hole for a headphone jack, or is the top left round hole? And all the round holes on the bottom are for the screen buttons? Thanks, just a little confused.