If you have the data plate and the drawings, it is legal to build a new aircraft around the data plate and put it into the air as "Restored".
Point taken. At which point does a restoration become a replica, reproduction, or - the latest buzz word of the vintage car auction houses - as "Evocation"! However, as far as the crush damage is concerned if it is possible to retrieve and restore "Glacier Girl" from under 150 ft of ice then there is a fair chance that securely crates and dismantled Spitfires may be relatively undamaged. I think they claimed to have used about 80% of the original of the P38.
As for corrosion/rot etc are concerned, if they were securely packed and protected then the corrosion may be limited. Have a look at the LSR car Babs, buried for 40 years under the sands of Pendine beach. Electrolytic corrosion had completely destroyed the aluminium body, but the rest of it was actually in remarkably good condition.
Pendine Sands
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