I'm going to continue to update this thread for easy reference in the future.
Yoshi's famous install thread:
#/f/tech-talk/72...o-install.html
http://www.360realms.com/S13-S15/
Here's an old thread about wiring up the s15 high and low beams correctly on an s13:
#/f/tech-talk/359768...am-wiring.html
High and low beam bulbs:
#/f/tech-talk/440351...placement.html
Beam adjustment:
#/f/tech-talk/347435...djustment.html
eBay hid bulbs into s15 non-hid housings:
#/f/tech-talk/274938...headlight.html
Decent write up on s13.5 conversion:
#/f/tech-talk/274938...headlight.html
Aftermarket s15 headlights:
http://www.240sxforums.com/forums/co...eadlights.html
S15 conversion FAQ:
http://www.jspec.com/s15conversion.html