Ability to paint objects that have 'flush into object' enabled

[choco3dprints]

Or rather, have the ability to paint on objects that are marked as flush into object. I know this is a big ask, but I'm wondering if it's even possible to do. I like using articulated creatures to purge into so I can save waste. But having the eyes painted would be perfect! could create a lot of neat effects too. Right now I haven't figured out a way to do it otherwise.