Print in TPU/SemiFlex with the side with the back facing down and the wider edge up put support enforcer blocks under the hex posts.
The author remixed this model.
Original was for Caddx Ant lite and to tight for Baby Ratel2, remixed larger hole for lens and cutout for the screw mounts so it can be pushed forward further.
Also original had holes for hex plastic posts, I changed mine to “M2*19mm Two-way Knurled Aluminium Standoff Black” (DIATONE) so the hole is round and 3.5mm instead of hex.
Some models of the AlfaRC or Rocky frame might have 18mm spaced round posts already (some variation in design and name on aliexpress etc.)