You've made some good observations ...
The color is filitered, but it works a little different than you'd think - the image reflects off the filter rather than going through it. Red LEDs do not work well during day light. They look great at night, but can completely fade out in the sun. You can't tell from the photos - but one of the reasons for the hand made LED array around the base FL HUD display is so that I could switch from the V1 red LEDs to bright blue ones. There's no need to compensate for the curved mirror - it actually helps line things up on the curved windshield. There is not a lot of room in there - it's easy to block part of the HUD display. That's why the circuitry for the clock and temp guage had to be outside the case. For the dimmer I brought the SR1 and V1 light sensors out into the open part of the case - so that they work normally. If you look closely in the pictures you can see the bare photo sensors.
FWIW - The U shaped LEDs around the base FL display (the last 2 pics) were a part of phase 2 - it worked, but not as well as I'd hoped. Part of the blue LEDs were being blocked - the HUD wasn't designed to have a light source outside of the main FL display. The new plan is to integrate them into the bottom piece of black plastic in the case - the piece that the SR1 LEDs are behind in the first set of pictures. That location works well with the mirror and places the LED image on top of the speedometer - a good location for a warning indicator.
Corvette Store
Mounting radar detector inside HUD.
