took down the wiring box. There is just one brake connection in there. Its where the main brake run is connected to the breakaway switch (ie. three wires, one from the main brake wire, one from the switch and one continuing on towards the brakes. I measured the resistance there and got the 1.0 at that location so that at least means that my "splicing" at the plug pigtail isn't more resistive than it should be.
Perhaps the "nominal" 1 ohm resistance is about as good as it gets given old wiring and magnets. Perhaps moving adjusters a bit... they haven't been done for about 8k miles might improve things.
