I'm not fully versed on all the things that would be needed, but at the bare minimum it would seem like you would need a bunch of automated processes for just the building - Import src packages, making sure that you copy in changes/patches when RHEL does. - Replace the RH trademarks in every package - Build every package and run verification tests for each arch - Build ISOs

You would also need I said if infrastructure servers that can scale to a large number of users for Yum/RPMs, etc.

Then you also need a set of servers for issue tracking and a way to break it out per package.

I wouldn't imagine that it is anything which can't be done, it just seems like there's a lot of little pieces that you would need to set up, and infrastructure you need to run.