Hi, I can let you all in on a few secrets after having sold several sets on Ebay in recent times, now I just don't have the time anymore, and it was a bit of a labour of love TBH.
This is quite time-consuming to do it properly.
First, get your clear lights, mask out the clear inners (I made an elliptical mask the exact size of the inners first with some professional masking film - it is a perfect ellipse, by the way very fiddly as the flim needs to be heated with a hairdryer then rollered to get rid of any creases) then attack them with a Scotchbrite pad to get them all nice and cloudy! -Yup, I'm serious, don't worry, -if you don't do this, the laquer will peel in several months or years' time...
Wipe them clean, then mask carefully around the edges with that blue flexy masking tape stuff, cover the rear of the light with brown paper. Then use a beeswax impregnated cloth to remove all traces of fine dust.
I made a cardboard holder to slot the narrow end of the light into to grip it firmly. Then spray the red tint (I used the E-Tech stuff off Ebay), about 4 good coats, spraying from about 10-12" away in a warm garage.
Tip: Wear surgical gloves and hold the light at 45 degrees, spray quite generously to avoid "orange peel" caused by being to far away/too little paint, drop the light to horizontal immediately after each coat for a few minutes to help avoid runs, it's a fine balance to avoid runs though. If you get a run, don't worry! You can let the light dry overnight, then gently rub down the run with minimum 600 grade W&D then Scotchbrite again, then respray. Don't rush.
After the light is dry, remove the masking, and rub down again with Scotchbrite to get rid of the "step" between clear and red roundels, check again for runs before you continue. Leave the masking on!
Then spray as before with 4 coats of clear (acrylic) laquer -I used Simoniz from Halfrauds, it gives a very smooth glassy finish. Again, don't be worried about runs, you will get it wrong the first time -I did!
The secret is, if you mess up, LET IT DRY, then rub down and start again! Don't mess about with wet laquer! If you let it dry, you MUST Scotchbrite to key the surface before you re-commence.
As you guessed, patience is the key, I'm a bit of a perfectionist, but the results are worth it even a close examination of the lights should not reveal they are anything other than OEM lenses. 8)
Have fun!