Whish I could help with the fine tuning your working on. My instinct would be guides to hold the cables in place. But.. where would the slack go? Or.. springs to take up the slack perpendicular to the cable? Sounds hokey though.

My brake handle mod feels nearly OEM. Has been working flawlessly since day 1. And I still apply it every time I park. Easy to access, easy to pull, and plenty of holding power.

https://thefactoryfiveforum.com/show...-Parking-Brake