Four ordinary red LED's in the back,
just filed the very top from round to rectangular
and flattened one side to fit.

One note,
take care with the stuff you file off
of any LED's.

if I recall, it's gallium arsenide which is not the kinda stuff you wanna
go breathing in, period.

Anyways, the lighting worked ok but
I never did get any decent pics of the cockpit sadly,
wasn't that great anyways so no real loss