Headlight Conversion

Nice diagram. You can buy the materials to do this as a kit from any one of a number of sources, or just get the stuff at your local NAPA.

The diagram shows a fuse, but I prefer to use circuit breakers for safety. Also the wire feeding the relays should be a 10 AWG wire connected directly to the binding post on the alternator. The H4 bulb will plug into your stock headlight connector, but if you go nuts on the wattage you may need to upsize the conductors.

Try a basic H4 swap and a set of relays before you go nuts with the bulbs, you will be quite impressed.