I am not sure that the processor is angled differently. In my photoshop overlay, the cpu/northbridge were a perfect match, so the clamp and the sink might still work. The Airport/Bluetooth cable definitely works between them. The audio board is almost identical, (it uses a new codec chip), but has the same rest of the chips and connector, so it might work. The hatch, on the other hand might have a different size, although I am not sure that it does, or that it mandates a change of the upper case.
While all of them have different IDs, it doesn't mean that they use different cable pin-outs or that they have different sizes. Out of sheer curiosity I noticed that the late 2009 MacMini Airport card can be used in the 1st gen MBA using the MBA cable, screws and everything, although it has different Apple IDs.
I do agree about the HDD and the HDD cable and about the hatch as clear dependencies. Maybe I should ask a friend who works at an Apple Service to give it a try.