Jules Richardson wrote:

We've got about 210,000mi on the car at the moment, and the clear plastic
lenses for the headlights are getting decidedly yellowed/murky after so
long - they're getting to the point where taping candles to the front of
the vehicle might be more effective

I keep seeing ads for some sort of restorative polish stuff (which may
well be snake oil) - but it got me wondering if a DIY concoction might be
worth a try - e.g. I've found in the past that combinations of toothpaste
and baking powder work very well for removing scratches from CDs, for
instance, but I wondered if anyone can recommend any other home
remedies? :-)

cheers

Jules
Problem is jules, that the yellowing may actually be in the body of the
plastic itself. Due to UV degradation.

Expect to have to buy new lenses, but try a bit of T-cut on the old ones
first

e.g.

http://www.autogeek.net/3mperllrubco.html