Rep! This is a unrelentingly brutal ride, I'm surprised you only resorted to the granny ring at the end! Apart from like box hill i probably used mine on every hill haha
I use(d) a piece of cardboard ziptied with two ties to my stem and a bulldog clip as a route sheet holder until I recently got a barbag with a clear plastic map holder. If you want to waterproof the above setup you can use a plastic bag.
Rep! This is a unrelentingly brutal ride, I'm surprised you only resorted to the granny ring at the end! Apart from like box hill i probably used mine on every hill haha