Custom ROM ATV (Android TV) for Vega S89?

[threehappypenguins]

I found two ATV custom ROM's for AMLogic based devices:

[ROM Image Firmware] MXQ PRO 4K - p201 - android TV (ATV) - by cOOLio
[ROM] Beelink GT1 Ultimate SCV2-ATV (Android TV) (DDR4)

Except I am trying to figure out whether they will be compatible with my Vega S89. I believe the Vega S89 is chipset S802 and that S812 would be compatible with it. But I don't know how to figure out what those custom ROM's are, and what else I need to be looking for to find compatibility.

I have an NVIDIA Shield Pro Android TV, and my parents and in-laws have the Mi Box Android TV. I don't think I could ever go back to tablet-based ROM's on a TV box. Android TV is far superior for the TV, in my opinion. And app development for it just keeps getting better. I want to fix up the S89 and give it to a friend.

[blunden]

It should technically be possible but you need to run at least Android 5.0 as a base. Given that there is an Android 5.1.1 firmware from another device that supposedly works decently on the Vega S89, that firmware could be used as a base.