lol, I completely spaced that tip... and you're right, I've hot wired a PSU for instances like these
You can read more about I used to perform this next update here,
recommended case modding tools
I'm installing an 120mm intake in the floor of our Lian Li's chassis
We first apply 3M Green (low tack) Painters tape before marking off the fan hole location. We're using a 120mm steel fan guard as out template for the fan hole with a measuring square.
The fan guard allows you to mark the center of the fan hole.
Using center punch to pin point center before using 1-1/2" hole saw attachment to accommondate Knockout shaft.
After cutting 1-1/2" hole for Greenlee knockout shaft.
Greenlee Knockout Punch for 120mm fan holes
Tightening Knockout Punch with Socket Wrench