The neck has some errors.
The part is too large and there is a step with the cabin. If the neck is actually flare slightly (with a diameter slightly larger at the end), this is here too pronounced. Having no tube with and correct diamter I could work one, I had to continue with the kit one, seriously modifying it (No photos).
Then, the end cut of the neck is incorrect, being almost top/bottom symmetrical on the kit where it should be more wider at the top. The angle is also incorrect. So cut the top side and adding plastic card on the bottom side.

To reduce the flaring, I cut a notch, then dipped the part in hot water to soften the resin and tilt the two edges to close the opening.

The bottom of the neck is rather round and the shuttle’s neck was not stable when inserted. So I milled inside to fix this. Then the neck became not enough long, so I added an 1.5 mm thick plastic card.

With these operations, the part became quite thin and fragile. Moreover, it will break a little later, to be repaired (after a search of the broken parts on the workbench).