Finished up the lenses, still need to glue the bio back together.
Looks nice Natrix!! And ya had guts enough to take the bio off and mod the lenses at risk of damaging it, sand that seam down and paint it. Just practice on old toys until you refine your technique.
On my HT P1 I used Krylon metallic silver spray paint as a base coat, and then just used a black acrylic paint washed down to weather it.
Easy as that. You can darken it up more, overall or in individual areas, with more coats of the wash. Mine looks a bit lighter than what it is because of the flash on my camera. If ya would go that route, make sure ya primer it first.