The Revell kit is big on size, great on shape and proportion (minus the head), and weak on details. See the pic for an out of the box buildup (thanks to Model Versium for the pic). Most of the detail that's there is actually pretty representative of the studio model (I won't say accurate), but at best needs refinement, and there are lots of greeblies missing. For this build I re-scribed all the panel lines, replaced as much inaccurate detail as possible, re-greeblied the belly, and completely rebuilt the head. I elected not to try to keep the articulation, since it ws to be part of a diorama. Some greebles come from random donor kits, a lot of scratchbuilds, and a 1/48 Tamiya Flakvierling. The studio model used a lot of parts from the 1/35 Flakvierling, so the 1/48 is a great source for this smaller model. This requires either several Flaks or a good way to reproduce parts, I cast some extras in resin.
Let's look at the head first. The kit head is a monstrosity, I'm not even sure how they came up with this rediculous thing. Using Baloo's blueprints and measurements from studio model pics I rebuilt the back section with sheet styrene. The disks on the side are epoxy putty using a simple push mold pulled off of an appropriately sized refrigerator magnet. The fins on the bottom are new as well, and all greeblies have been replaced from scratch, staying as accurate as is reasonable to the studio model.
The guns were the really fun part! The side guns are made from bits of plastic sheet and tube, 1/48 aftermarket brass Flakvierling barrels from RB Models, and the 1/48 Tamiya Flak guns. The brass barrels really sell the scale, these are beautifully delicate.
The chin guns were a lot of work! I built one and made a mold for the second. It's mostly epoxy putty with plastic detailing, and the round/wheel part salvaged and modified from the parts that came with the kit. The barrels are 1/48 aftermarket King Tiger barrels from RB with the ends filed to the appropriate shape. Once again the brass barrels are a perfect choice, these look so great on the model.
It took me 3 or 4 attempts to get the cockpit window shape on the face right. The studio models had slightly different shapes here, with the larger model having a more squinty look. My first one was not narrow enough, the next not long enough, etc, but I finally got it right. What's that in the window you say? While I had the face off (repeatedly) it occurred to me that I should add a cockpit. I made a quick mold of the really nice pilot figure that came with the Revell Tie Interceptor pocket kit (cool model BTW) and cast a couple in resin for the cockpit. With the window on you can barely see in there, so I painted them rather sloppily, added a console greeblie to the center, and left the rest of the interior alone. I'll never see these guys again, but I know they're there. :)