With the structural restoration mostly done, most of the people who have been working inside Namdaemun the past few months have been painters. They are overseen by Hong Chang-won, a historian and expert in Korean traditional ornamental painting, or dancheong.[...]
“It’s difficult to know what patterns were originally used” on Namdaemun, he said. “There are few examples left of early Chosun dancheong.”
He found some in a temple called Muwisa, in Gangjin, South Jeolla. The most noticeable difference is the paintings then were green and blue. Red and yellow did not become common until later in the Chosun period.Some photos of Muwisa Temple can be found here and here. One good thing about what happened to Namdaemun was that it allowed archeologists to dig around Namdaemun's foundations and turn up interesting things.