One person contacted me about the measurements for where the JDM vents go in the hood. Since its a lot of work to measure all the shit out I figured I'd post here and hopefully it'd make it into the "How-To".
My hood is brand new, the vents are brand new, your measurements may be slightly off, so I measured from where it would be most universal.
All measurements are in millimeters.
I measured and cut the hood in half from front to back. I did this across the washer nozzles and from a random spot in the middle of the hood (in my case at the top of the vents). If you don't want to write on your hood, use masking tape.
Measure from the very back of the hood (put a small piece of masking tape around the end of the tape measure to prevent scratching) toward the front, put a mark at 683.5mm. This will be the topmost part of the vents (see picture).
Measure out another 153.5mm (total of 837mm from back edge of hood). This is the lowermost part of the vents.
Mark or mask out from these two points, forming a "T" with the centerline.
Now, from your centerline, measure out 34mm each way. The vents are 68mm apart at all points (inner edges are parallel).
Once you're in this area, mark and cut however necessary.
On the "real" JDM vented hoods the mounting points are recessed, so I don't know how you guys plan on mounting them to a flat hood.
The vents do not lay flat on the hood, they are turned "in", like scowling eyes. Hopefully that can be seen in the picture.
In the picture, I mostly measured in CM, and I corrected some of them as I wrote this post, so don't let the numbers I have written on the hood confuse you.
Just remember to measure like 6 or 7 times, and only cut once.
Any questions or confusion or different points you want me to measure from let me know.