Before drilling more holes in the panel, I install the left rib on the subpanel.



I also draw where the subanel needs to be drilled for the radio trays. The bottom edge of the ruler shows where the lower edge of the trays will be. It will stick a bit below the subpanel.



Then I do some drilling on the left side of the panel : the two trim indicators, the pake brake handle and the magneto switches. I still have to chose which cover I will use.



In the middle, the autopilot switch and the mini switch to change the autopilot GPS source.
I also mad a small cutout on the lower left side of the altimeter hole for the adjusting knob.



I then drill the U-channel the supports the switches and engine controls. I also drilled the holes to screw the U-channel to the pannel.



Then the last big holes for the alarm lights. They are normally installed as the red light but I'll try to install them as the yellow one.



To do this I fabricate a small bracket with two shims from leftover parts.



I this is the result. After some small teaking it should look perfect.