Man, this thread has just so many abbreviations, its crazy! Anyway, theres not much activity in this forum section and I thought I'd post my progress on my HVAC center while I'm waiting for glue to dry.
My old modifications, over a year old were starting to fail. I guess I built my voltage regulator at too high of a voltage.
Split that HVAC unit open, Yumm.
I drilled holes into the diffuser to fit the 5mm leds into, and used tinfoil to help these super effcient optics
.
Glue of choice, support your own economy, dammit!

It sets quick, yet I would like a higher initial viscosity, too runny for such a small application.
Similar approach to how I did my instrument cluster lighting. Uses a lot of LEDs though!
If there is something different I would do here, is to raise the LEDs by a 1/8 to a 1/4 of an inch.
Results are pleasing so far.
thermostat dial, glue needs to dry then I can begin soldering.
Same story with the glue.
EDIT: Glue dried on some parts! (or well, dry enough for my low standards!
Then again, I'm probably the only one on new-years eve drilling holes in their car to install more lights!
EDIT: Its done enough!