I had also originally intended to use the AH PE platforms (which utilize only the open struts for support) to replace the kit plastic on the lower level. After reviewing all the research and reducing the platforms, I realized that doing so would not be appropriate for my build. So, I used only the kit pieces depicting the solid portions of the platforms with their molded-on support trusses. I had considered replacing the remaining support trusses with brass PE versions, but doing so seemed of marginal value to me, given their scale size and the sheer number involved.
I then modified the six sponsons for the 10cm main AA batteries. I removed the kit plastic trusses under the platform and substituted brass trusses. Removal of the styrene trusses was challenging, because each sponson actually has a shallow lip that protrudes down off its front face. The only way to scrape everything off without damaging this piece was work form the rear by cutting off the curved support members at the rear, removing all the trusses, then reattaching those same curved members. Fun.
The kit provides a pair of paravanes to be placed forward of the main battery positions on the lower platforms. I had always assumed that these paravanes were launched by the usual small paravane davit, but in researching it and re-examining photos, I was surprised to learn that my assumption was wrong. It seems that all the Japanese carriers used one or two booms attached to the hull or sponson, and not davits, to deploy the paravanes. I don’t know why. I’ve apparently been misinterpreting photos & misrepresenting this detail on models for the longest time. So, the corrected depiction is how it’s represented here, along with a small deck winch for each set of paravanes.
There are multiple platforms for the 25mm AA batteries, all mounted at the same level as the 10cm main battery. Each platform has 1-3 tabs on the inner edge meant to fit into alignment slots cut in the hull. Sadly, the fit for many of them is subpar. Much subtle trimming and sanding was required to get the platforms to fit flush with the hull. Even so, there are noticeable gaps around the joints where the tabs enter the hull. Much of my time has been spent filling the crevasses.
I also came to the same decision regarding replacing the support trusses with PE versions – just not worth it. For the most part, very little of the trusses came be seen in this scale when the model is posed in its normal configuration unless one is looking up from very close-in. An exception would be in a diorama, with a ship in a more dynamic pose. The best example that comes to mind in marijn’s stellar Amagi diorama:
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