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Is there any way to "tint" the cockpits on vehicles?
Did a quick Google search and found this.Model Making Resources, Working With Clear Polystyrene Parts and KitsTinting
The best way to tint a clear part is to airbrush it with one of the special clear colour paints or with a mixture of varnish and coloured ink.
Some aircraft have metallic tinted windows and this can be replicated by airbrushing the inside of the canopy with some on the almost clear carrier fluid from a tin of metallic paint that has been allowed to settle.