So what I gather is the tops of the big guns are deck blue except where the 5-O is noted and all the upper decks are deck blue?
Yes. Where the diagram indicates that parts of the turret tops are 5-O, they should be painted in Ocean Gray. But the decks aren't all deck blue. Where 5-O is noted for the decks, all horizontal surfaces within the 5-O demarcation should be painted in Ocean Gray. It looks like there are four areas where this should happen--at the stern, at the bow, starboard aft near and ahead of the third 16 inch gun, and a small area on the portside amidship.
Here's a link to another build of Missouri over at model warships. You can see the 5-O pattern on the decks.
http://www.shipmodels.info/mws_forum/viewtopic.php?f=60&t=76709
I got the Taymia paint numbers for deck blue and used them to mix the red, green and blue and I think I got real close. I will take photos later as I messed up the masking of the rear deck. Not a problem to fix at all just some re-painting.
Yup, know how that goes. Painted BB-55's three main turrets today, and my masking was less than successful. Will have to wait till the paint dries, then try it again.
I like the Taymia tape. It has worked real well for me and have not had any problems at all. I need to get some more as I am out right now so regular masking tape is what I got.
Well, I think I'll give Tamiya a try. Part of the reason for the mask failure today, I think, was that painter's masking tape is too thick to conform and shape around details like life rafts, which were molded on the turret sides. I got far too much overspray.