Nice to see someone else taking a crack at it!
Thinking back to the Spitfire guards I had in the past - and I may be mis-remembering, here (if so, sorry) - I seem to recall there being a bit of in-development chatter that the mix of colours included clear bits as well. Poured/dropped in at random and brighter "droplets" dripped in to the clear, so they'd hold a bit more of their integrity and contrast against the reds/oranges. Some of the deeper, more defined areas of the earlier, thicker guards I had seemed to reflect that process.
And then, there was the addition of the thin, clear top-lam surface. Not sure if that still happens with the newer guards, but I remember the earlier ones delaminating around the screw holes.
Of course... once you get the technique right... you HAVE to make sure you get the angle of the bevel right...
All the best!
