Ill try to be totally clear

The Aoshima kit is totally inaccurate in the upper decks of the pagoda. No amount of pe can change this. Its not a little different in 44 its totally different. The decks are much larger rebuilds outfitted with more optics for AAA. You must totally rebuild these decks to make a 44 Yamashiro.
The Flyhawk pe looks great and fits the kit well. As such you will build a totally nice 1942 Yamashiro with it. In 44 the pe is totally wrong in the top 3 decks of the pagoda. Nothings going to change that. Flyhawk used 42 references same as Aoshima and faithfully made the wrong pe set.
Modified you can use the searchlight gantries but these require some alteration. Their plan profile is not a T as in the kit it is a rectangle in plan. Youll find this out quick enough when you bend them into shape and they dont fit
This is of course without mentioning the AAA additions to the ship. I cant remember how many 25mm and 13mm guns added. like 40 ish . Its been a long time I cant remember.
Frankly building a 44 Yamashiro with the Aoshima kit is going to require scratch building. References of the Yamashiro in 44 are very poor. Personally Id chalk this one up to experience and buy a Fujimi kit. It has some minor errors around the rear hull bulge and anchors. Fankly a lot easier to fix than pagoda decks with poor references.

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