So i've read the mad electrical writeup where they find the two big power supply wires that pass through bulkhead, one red and one black right? Then they remove the spade connectors, drill out the locations through the bulk head, and crimp/solder/insulate extra length of 10ga wire so that each respective wire now passes right through the bulkhead without having that weak spot.

Now I've also seen "Nacho's parallel bypass" mentioned but can't find the writeup. Is this one just a matter of splicing along the main power wires to connect the two sides of the bulkhead together without removing the spade connections from the bulkhead?

Which mod is better?

Currently I have run a power wire from alternator output to positive battery stud with appropriate size fusible link. I did not bypass the ammeter because it has never given me problems and I prefer to keep it functional. I'm getting ready to install a higher (especially at idle) amp alternator, and the bulkhead bypass is my last upgrade right?

Which one is better the parallel bypass or the drill out mod? Am I missing any steps from either mod?

Thanks
roe

If it's working, why mess with it?

Now, if the higher output alternator is to run some high load items inside the cabin (amp, rear window defogger, heated seats, whatever), that's one thing; maybe the wiring upgrade might be necessary.

But, if you're doing it to run more stuff underhood (electric fan(s), headlight relays, foglights, etc.), that's something else; upgrade (or pass-through) of the bulkhead connector might not be necessary.

You can take some load off the bulkhead connector (and headlight switch) by putting the headlights on relays, BTW. (Takes a little of the load off the ammeter, too, so it will not necessarily indicate true charge/discharge of the batt. But any bypass will do that.)

I didn't feel that the ammeter was all that useful, so I changed mine to a voltmeter ('72 RR, FWIW).

Yes, there is an amp and stereo in the car. Also, anything to make the car safer is a plus in my book. I also have electric fans, aftermarket guages, and would just like to eliminate that bulkhead fire hazard. And once, on startup I had a small amount of smoke come from the bulkhead area. I think power was being pulled through bulkhead for the stereo, fans, etc because the car had not been started and there was too much power being put through those little spade connectors. Don't want to drive it again until this is eliminated.

Bulkhead parallel bypass. This is a safe upgrade since you are swapping to a stronger alternator, and your ammeter will still work.

Got this form John (Dads426) I will be doing this soon. It's a good link for just what you want.
http://www.madelectrical.com/electricaltech/amp-gauges.shtml

so with your exterior bypass, the only thing you need to worry about is how much power is moving through the bulkhead and the amp meter.

if your fans are wired off the battery or starter relay, then that is less passing through the bulkhead.

lights on a relay, even less. so your amp meter isn't over pulling power.

but they eventually fail, so you would be without power to start the car till you bypassed it. not a big deal I guess. I bypass them in general.

so the mad bypass where you make it a solid wire through the bulkhead helps, but I prefered to eliminate it entirely with a solid bulkhead connector. bit over kill, but I decided to do it due to the electric fuel pump and power top both pulling power inside the car.

https://www.pegasusautoracing.com/productdetails.asp?RecID=2848



then I cut the bulkhead connections for power and wired them to the connector.

I can then wire other things to it for direct hot to the battery inside the car, eliminating any power drops.

Ok, I see how the parallel bypass goes from the battery and alternator output to the Ammeter. If any one of the two options is better I guess it would be the bulkhead upgrade with the solid wire running through. My reasoning is that you aren't just bypassing a problem area, you are removing it. So if I only do one of them it will be that one..

Is it recommended to do both the bypass and the bulkhead upgrade?

Also can someone explain the headlight relay? I installed a relay to power my electric fan where the keyed 12v powers the the relay, but the juice to the fan comes from the output of the alternator through the relay. I assume it's the same with the headlights. I just don't know what wires are the power wires to the headlights that need to be switched to a relay. Does anyone have systematic for that?

it is generally both. again because the amp meter failure drops all power inside, and most people run more powerful alts and the amp meter was only rated for like 50 amps. so more power could burn it out.

for headlight relay you need 2.
http://www.mymopar.com/downloads/1971/71SatelliteGTXRoad%20RunnerA.JPG

your wiring diagram shows a red and violet line.

I just cut these and used them to turn power on to 2 different relay's then powered the lights on the other end of the cut from the relay.

since I have the bulkhead fitting for power, I ran all my power to there for stuff off the engine compartment side through fuses.
so headlights would route off that through a fuse block.