Re. Head lights always on...
Sounds interesting, but...
Since I bought my first car ('69 Bug), and every car, and 2 motorcycles
since, I have ALWAYS driven with my headlights on. Can't image the few amps
they pull are anywhere near what an A/C compressor pulls which I believe
typically drops MPG by about .5. In 63k miles I've driven my 5kCQ I've had
to replace 3 halogen bulbs - cheep insurance in my book, and doesn't require
any special circuitry.
Benjawan Kuecharoenwong made a similar suggestion in his posting, but
suggested using the first of the 2 detents on the light switch -
unfortunately in some states (Calif for instance) those are considered to be
the "parking" lights, and it is not legal to drive with just the "parking"
lights on - it's either full lights, or no lights. Don't want nobody having
unexpected conversations with "smokey"...