The 80s refits of the Iowa class ships changed some of the fabric of the ships.
Notably, superstructure decks were extended to mount missile launchers, and also some platforms were extended to mount commo gear. This makes for a complicated dance, as many of the decks will need cutting down. At least there are very few areas which will want adding on.
The masts are going to be an issue, as they have extensive changes.
It's almost easier to convert a WWII BB-63 to KW than an 80s version, though. The chnages to the fire control radar were minimal; the surface search and sky search main radar were at least similar.
Now, as to the paint scheme being "simpler" that giving me head scratches. *0s paint scheme is Modern Haze Gray verticals, Deck Gray (where not wooden) and some Flight Deck compound aft at the helo area.
KW paint scheme is Haze Gray for verticals and Deck Gray for decks (wood deck un painted) and "Non Skid" in the aircraft area. There's debate about which Haze and which Deck gray those are.
From Navsource (April 1951)
To complicate matters, during the KW, Missouri (as did all the Iowas) had all of her 20mm removed, along with many of the splinter shields and "pulpits."
See navsource (Summer 1954)
(Not surprising, the 20mm only had about a 2000yd range, about 2 seconds' flight time with 300kt aircraft; only 1 second with 600kt a/c, making them pretty pointless against KW aviation assets.)
My father's 1st Class Midshipman Summer Crouse was on Missouri in 1953.