Planet X Exo3 compatible headset topcap replacement

The headset topcap on my Planet X Exo 3 TT bike wasn't the greatest example of this part, so I reverse engineered it and made my own. The bike is otherwise good but this part was not up to the standard of the rest of the bike. The original had the hole drilled off-center and would bottom out against the stem before getting enough bearing preload, so the headset would always be slightly loose. Someone else might have this issue so hope this model is helpful - if the stem is coming lose this might help.

Photos show the replacement and (in one photo) the original.The original is being held in my fingers, and you can see how the hole is off centre and the supports for the bolt are uneven.

To make this part work you will have to print in a stiff material, probably a carbon-fibre enhanced plastic. I used ColorFab XTCF20 and this works well. Normal PLA, ABS, etc will not be stiff enough and will bow when trying to set the preload. Print with plenty of perimeters, top/bottom layers, infi