I too shoved it in the seat post with some folded duct tape as filler to keep it tight.
Also got my speedmax on the road finally with the Aeria Ultimate stem and hydration. I'm using the 25mm spacer, di2, Tririg brake. Looking super clean.
My bike mechanic found the internal cable stop and noodle for the front brake was causing too much friction in the brake, so he decided to use the jagwire outer to get it thru the stem. My biggest peeve on the thing is how the bento moves around because of the cables moving about as you turn the handlebars. I wonder if there is a better way....