Restoring a dual snorkel air cleaner

[R/T's 4 R/P]

For those of you who have restored a four barrel, dual snorkel air cleaner, how have you handled stripping the part and not messing up the vacuum doors
Also, it appears as though the lid was zinc plated before the top was painted. Is that correct?

I've painted a few, so I'll have gotten much better on the wrinkle black finish, but I'm wondering about the prep of the rest of the body of the air cleaner.