I fitted the cabin top center support and drilled the holes into the cabin top.
I 3d printed a drill guide to keep the holes perpendicular and parallel. I started with 1/8″ holes, then drilled to 3/16″
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220904_0201343054367612271801279100.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0309546391702331203930051789.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220904_0201224003932052614735318944.jpg)
I then match-drilled the holes from the upper forward into the center support.
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0304377722451213802969723664.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0310001027598157343569287965.jpg)
Next, I 3d printed another guide and drilled the final 5/16″ holes into the cabin top. I cut the aluminum spacers to length, hammered them in so they were flush on the underside, then countersunk the holes on the exterior.
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0228414017366157075190177081.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0227448874504577164265141788.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0228012855320550399915890309.jpg)
Everything came out great. The bolts slide in smoothly through the cabin top and into the holes in the center support.
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0228545155745762680583565183.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0322143832631870102862115156.jpg)
![](https://airplane.allanglen.com/wp-content/uploads/2022/09/pxl_20220907_0313052661026417478855416097.jpg)