AB-BN Endoscope Mount

WIP: UNTESTED!!

I modified the AB-BN cover to allow a 5.5mm endoscope to be mounted, I was asked to mod this by someone in the FB group after sharing my modded SB cover, I do not have an AB so I am unable to test if it actually works so feel free to leave some feedback and let me know if something needs to be tweaked or if it just won't work at all so I can update or remove the models as needed. Hopefully this is useful to someone :)