First, I'd recommend you do this to a vacform canopy. Typical styrene's going to be too thick to look convincing once you start putting holes in it. Poke a hole with an old airbrush needle or a pin or something, then "jag" it up a bit with a #11 blade. Best I got...
On the Bench: 1/32 Trumpeter P-47 | 1/32 Hasegawa Bf 109G | 1/144 Eduard MiG-21MF x2
On Deck: 1/350 HMS Dreadnought
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