I have seen on another forum a method where you dip cotton wool in boiling water and use this to press the decal down, the heat helps the decal to conform to whatever's under it. Rubber gloves are recommended and I use the little circular pads of cotton wool that are sold for removing makeup. I've used it few times fairly successfully with Airfix decals though never on anything as big as that fairing under the roundel.
Hope this helps,
Simon
Hope this helps,
Simon
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