I've added a rubber grommet to a hole in each axle mount bracket so that the brake cables running through the brackets are protected. I've run 12 gauge cable to each brake. heat shrink tubing protected crimp-on butt connectors join the magnet wires from the brakes to the trailer side of the brake wiring. I've used commercial style electrical crimp sleeves to join the cables from the brakes on both sides with the cable that runs to the junction box at the front of the trailer. A plastic cap protects these crimp sleeves and I've added multiple coats of brush-on "electrical tape" to encapsulate the caps and wires that enter the caps.