Looking good!! The Pikestuff buildings are great, and easy to use. I have several that I have turned into different HO scale fire stations. Hadn't even considered getting one for a 1:400 hanger, but I just might have to now.
May I offer a suggestion? I don't know if you plan on doing anything to the door, but I have used very thin Evergreen strip styrene on my fire stations as a combination of a trim piece and something to hide uneven cuts. I just surround the large doors with it, and it really adds to the appearance of the building. Just a thought.