I undertook this project as a result of a number of JHPS Bulletin Board postings concerning the burnout of JH switches, overloading of circuits, and the desire to make sure my headlights receiving the maximum amount of power, as directly from the battery as practical. Also, importantly, you will retain all the functionality of the original system - shutoff, dimming, dipping and high-beam indicator.

Let me say, up-front, that I did not replace all of the headlight wiring with heavier guage, as some people suggested - I was more interested in protecting the (expensive and vulnerable) circuits and switches than in assuring that I could get the max out of high-powered, replacement headlights. And I have been happy with the results.

Here is a step-by-step tutorial along with some pictures and wiring diagrams to help.

1. First you need to buy a couple of relays. Although you can probably find them
     lots of places, and perhaps of better quality, I chose to buy mine from J.C.
     Whitney, because they were easy to order on-line. Just order two (one for high
     beams and one for low beams) of the following:

     Heavy Duty Headlight & Accessory Relay Kit
     30 Amp, 350 Watt Capacity
     SKU# 14ZX9433Y
     $ 7.99 each

     These kits have both the relays and the wiring harnesses. If you are less
     adventuresome, you can order a couple of spare relays for $4.99 each too,
     and drop them in your tool box - I did.

2. Next, print and study the following wiring diagrams of the relay installation and
     locate the appropriate wires and points on your car.

1. Headlight Circuit
2. Headlight Dip, Horn, Clock Circuit

3. Find a good point on which to mount your relays. I mounted mine using two
     holes that already existed off to the side of the side of the radiator and in front
     of the radiator mounting panel. (See picture 1)

4. Prepare the relays for installation. I would strongly recommend doing as much
     preparation as possible before mounding the relays in the car. I measured
     how far apart the mounting holes were, and then mounted the relays, with
     harnesses attached, in my vise at that measurement (See picture 2). Next, I
     scrounged up some wire (color and size to match the relay harness wires)
     and made the red wire connections as shown (See picture 3) . The red wire
     supplies power from the battery to the lights so make it long enough to reach
     a power junction somewhere (I chose the bolted connection on the starter
     solenoid) and install a socket for a 30 amp fuse in it, as well. I chose to solder
     connections rather than use crimping connectors because I wanted to be
     sure there was as little voltage drop through the circuit as possible. You may
     also need to solder extensions to the white, green and black connectors
     depending on where you plan to cut into the “old” wiring to complete the
     connections. At this point I also marked one of the relays “low” and one “high”
     to make sure I got didn’t get the wiring confused.

5. Disconnect the battery

6. Mount the relays using a couple of nuts and bolts with appropriate lock
     washers, threading the red wire through the panel and into the engine
     compartment (See picture 4).

7. Complete the wiring connections per the wiring diagrams in step 2, above.

8. Connect the red wire to a good power point in the engine compartment
   (See picture 5).

9. Tidy up the wiring on both sides of the radiator mounting panel using cable
     ties (See picture 6).

10. Reconnect the battery, cross your fingers, and try the headlights. Now the
       only headlight current going through your original wires, connectors and
       switches upstream of the relays, will be the very small current needed to
       activate the relays. They do the rest of the work

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