Lol, how did you know?
It's all fitted, and I'm pretty sure it's leak free now. Entirely my own fault; I should've known better, I re-used the OEM clamps on the Bleed block.
Rookie error.
Ended up stripping right back to the valley, as I wasn't 100% sure I didn't have a leak on the bottom AN fitting. Ended up the coolant was sneaking down the inside of the Fireproof sleeve and pooling behind the plate in the valley.
Hose was perfect length, and with a tiny amount of detergent and a cup of boiling water to soften the hose; went together without issue.
EVERY SINGLE PHOTO I took has somehow been deleted from my camera, (4 year old camera aficionado to blame here), and I'm not pulling it down again.
I haven't had a chance to drive it far yet, so I'm not sure of the improvement, but going by the slug of air trapped in the valley; it can't be worse.