There's still some scope complexities you may need to sort out, but you're on the right track at least in current Ignition versions. I'm guessing/hoping there are going to be some updates in 8.3 as they move to a more git friendly setup for the configurations. But IA would have to comment on what the future holds.
This is essentially the function you need.
This forum post was most of my reference for doing the opposite of what you did(saving images), but should hopefully help get the Gateway and Image management.