1- what barry posted is good to save the headlight switch BUT JUST THAT... as stated by Nitrous, high power is still running thought floor dimmer switches. We need to note that relays are to save load FROM SWITCHES since those are the weakest points. with that mod you still are using A SWITCH ( even a selector ) to feed headlights.

Maybe that would work to regular beams, but definitelly NOT WITH HALOGENS or higher consumption lights kind.

2-wires and terminals EVEN SPADE ONES support the halogen and other higher consumption lights. In fact if you think THE ORIGINAL RELAY SETUP ALREADY USES spad ekind terminals, then why worry about bulkhead. Bulkhead is to worry on more than 40-50 amps loads. headlights never gets that. So once again as stated, relays are to save internal points of stock switches what are the real weak point.

3- feeding from batt will get wrong reading on ammeter and will overheat the bulkhead and ammeter since alt will be constantly recharging batt even when is not the bat what needs to be charged. Relays would it be the devices what simulates the batt discharge being on that side of the charging net. Feeding relays from alt side will make the load keeps OUT OF THE AMMETER.. of course that is if and just if you have a plenty powerfull alt. If not, then batt will be the device feeding and then the problem is backward, but still the same original had.

BTW have all my relays inside the cab and still being feeded from ammeter stud, alt side. WORKS CHARMING!!!

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