I guess there's no option but to just do it internally if that's what you want, but it might also be pretty subtle to put heat shrink tubing or something like that on the gear cable on the downtube and route the taillight cable in it to the rear mech. And then drill the racks leg for the cable.
I just got a dynamo taillight too, and put the cable under the rear brake cable clips I have on the top tube, as there's no braze ons. And am looking for alternatives.
I guess there's no option but to just do it internally if that's what you want, but it might also be pretty subtle to put heat shrink tubing or something like that on the gear cable on the downtube and route the taillight cable in it to the rear mech. And then drill the racks leg for the cable.
I just got a dynamo taillight too, and put the cable under the rear brake cable clips I have on the top tube, as there's no braze ons. And am looking for alternatives.