Eskimojoe: You can't really just re-skin the cockpits of these older planes. I redid a P-40E with updated instruments, dials, etc... and in the end had about 50-60 files in the submission. HTC rejected it.
On top of that, these old files split cockpits up into 2-3 parts because they were originally 256x256 resolution. Now we do everything in 1024 resolution, so when you submit you're suddenly using up to 15x the resources just for a single cockpit.
256x256 x 3 files: 196,608 pixels
1024x1024 x 3 files: 3,145,728 pixels
They don't like redoing the old files because of the way it's set up. Newer cockpits they seem to accept (ones where the entire cockpit is all in a single bitmap, like 109s, 190s, etc), but these older ones they seem to frown upon because just the act of reskinning them increases the hit on system resources.
cgar: We don't really do that work. That's all on HTC's end. They do the modeling and skin setup. We (the skinners) just take that and work within that limitation, within how it's already set up. Nothing we can do to change the 3D shape.