REAR PSI.

The rear PSI is one of the most difficult cuts on the dome. This is because the rear PSI is exposed, and all of the other holes, are covered by the outer dome, which is laser cut. Since everyone can see this hole, it's important that it looks good and is round, otherwise, everyone will know! The rear PSI measures 51mm across. The general way of doing is, is to drill holes, and then carefully file until you get a nice round circle. However, after looking at all the other holes I did today, none of them were particularly "perfect". So, I decided to improvise and try something else. I went and a used a hole saw that measured 44mm. I then created a "perfect circle" inside the outline of the circle that I had created from tracing the template. Since I had a perfect circle, filing was a lot easier since I already had the shape! Here are the results... To show you how perfect this is, I held up my PSI housing behind it, and took some more photos. The housing is now ready to be installed! I have to enlarge the front PSI a little because the housing sticks through the inner dome and sits flush with the outer dome. The rear PSI sits FLUSH WITH THE INNER DOME. That's important to note.