Problems can occur with Amber bulbs depending on the quality, the coating can crack and even fall off mixing white with the Amber light overall reducing the Amber content.
Tarka has amber bulbs and clear lenses, as fitted by the factory.
I've never felt they were either dim or just a point of amber light.
As a result of this thread I took the cover off the O/S front one.
The amber coating is starting to crack and there is no reflector, just the metal of the light fitting.
So, I'll buy a bottle of amber clear lacquer from Halfrauds and re-coat the bulbs.
I found mirror coated 0.3mm plastic sheet on Amazon, self adhesive. So I'll make up reflectors for the 4 indicators and the brake/stop lights.
The pack is 24 6" x 6" sheets for less than £8.00, I'll need no more than 6 and if I can get 2 per sheet, only 3.
I'll report back when I've worked out exactly how to cut and shape the reflector.