I have a Rail 5 on order from Trek Bristol and I have also just received a retrofit kit. Trek Bristol kindly offered to fit the kit before I collect. I’ve noticed there is a Rail specific top tube mount, would I need a controller with a longer wire to use this mount? I spotted in another thread that someone did in fact fit a controller with a longer wire but I’ve not been able to find the part. Is this part necessary and if it is, does anyone know the part number?