just to add another data point etc...

I followed Ken Lewis' lead in my wiring upgrade but I did not replace the
wires to the lamps themselves (was lazy).

full details and diagram here :
http://www.members.shaw.ca/albell/mods/lightcircuit.html

The point is that the short run of 16 gauge wire from my relays to the bulbs
is a compromise but I found it wasn't that much of one. I can't remember the
measured voltage drop, but it was MUCH less than the stock light set-up and
my lights are, and remain, bright! (100/80 bulbs, E code H4 lenses).

It has been in place for abut 2 years now, with no probs.

As others have stated, t is well  worth doing even if you do not upgrade
your lights.

Alistair

--
'82 Westy -> diesel converted to gas in '94
albell@uvic.ca
http://members.shaw.ca/albell