I have put the two relays behind the LHS headlight as suggested above. I used the type with an integral mounting lug, and just a cable tie through this for mounting, this works well as it hold the relays "upright" meaning if there is any water ingress, they drain. Then the whole relay and plug base is taped and heat shrink wrapped.
Additionally, I eliminated the fog light, making this a second reversing light. Then I used the fog light circuit to switch a third relay, mounted with the above. This relay takes its active feed from the high beam switched circuit, and feeds my driving lights. This allows the fog light dash switch to become a very OEM appearance driving light switch, without my even needing to access the dash panel, i.e. without much effort. I picked up the fog light circuit under the driver's seat.
I have LED headlights and driving lights, so this works well. If using higher current conventional style lights, then a second high beam relay, one for the headlights and one for the driving lights, would be preferred.
