When I built my Airfix A-26 a couple of years ago, I indeed painted the inside of the canopy black. To me that made a lot more sense than trying to scratch a cockpit in that tiny space. Looks good on the shelf too.
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I guess I shoulda blown the dust off before I took the picture.
BTW: Does this qualify as close air support? This old kit (1983) has been hanging around for a long while and it needs to get built.