To do skins such as Rosies Riveters we'd first have to get confirmation from HTC as to whether or not they'd accept a skin which was flown on a different model.
There are very noticeable differences with earlier B-17s that may discourage HTC from allowing them. The B-17Gs had the following additions in comparison to the Fs. The Gs had dual .50 cal nose guns and nose turret, staggered waste gunner positions, and I haven't seen any earlier models yet with the cheyenne window. The Fs had a single .50 nose gun, no cheyenne window, no staggered waste gunners, open waste gunner postions(may have had late war mods for this though), no chin turret, and last but not least they had a single .50 in the radio gunner position.