308 Headlight Upgrade - Help!

Just got an '81 308 that needs to be inspected. I have a headlight out so I thought I'd do the headlight upgrade that's been talked about on this forum that involves installing a new relay and improved headlamps.

I searched the site, but the info available is overwhelming and difficult for a newbie to follow. I waddled through so many pages and pics that my computer locked up ( I'm on dialup) and I still dont' know specifically where to start.

Would someone be so kind to list the specific items, sources, and maybe a step by step or at least a description of where in the wiring the relay needs to go?

Thanks