Courtesy of a regular correspondent, some interesting film of a very well-preserved Ki-54 discovered 320m down at the bottom of a freshwater lake in Japan, here, here and here.
Tail emblem appears to be from the 3rd Chutai of 38th Sentai/Dokuritsu Hikotai. Note white senchi hiyoshiki (戦地標識 - war front sign) fuselage band and plain Hinomaru. Upper wing and tail surfaces seem to be coated with silt (?).