Thanks for the response. I'm looking into cases where people used the AVOJDM kit and it seems like It also requires modification to work, although it seems like less work than the extensive 3D printing you did.
I'm primarily trying to make sure that this kit can hold the head unit in in a way that it wouldn't just fly off in a crash and concuss someone, or that it is held securely enough that the mount won't just break itself over time.
https://www.subaruoutback.org/threads/2005-2009-outback-legacy-radio-kit.374193/
https://www.subaruoutback.org/threads/2005-2009-outback-legacy-audio-system-upgrade.380226/#post-4359026