I’ve done several touring and rando forks with wiring braze-ons of various sorts, the one I like the best was loops of bent stainless steel spokes brazed on at the correct angle to allow the wire to run nice and straight down the fork legs. These open loop fittings allow the wire to be inserted or removed easily. This particular one was for SON wiring which is thicker than B&M’s, so it runs straight nicely down the back of the fork.