The one thing I did do with the engine lighting is
use a funny quirk that clear epoxy 5 min glue has.

if a small drop is put in one end of a tube it
forms an almost a concave lens like thing.
it works better if some colouring is added to the resin.

in this case, a drop or two of Tamiya clear orange in the mix.
it seems to form a hot spot with a dark ring visually.
Looks nicely different from bare LED light with almost no effort.
My kinda modeling when I can get away with it.

Which is not as often as i'd like but can't win 'em all.