My dad got a 18 L5P and I wanted to do an actual lift instead of a leveling kit so he can launch it without having to lower his torsion bars. I was looking into a cognito 4-6 but their front shaft can't handle launches from what ive read. And the factory shaft might vibrate if I go over 20mph. Is there someone else that makes a 4" lift kit that'll use the factory shaft? I'd like to be able to run 35x12.50 but I'm not sure if they would fit with only a leveling kit. Also does anyone know if they made changes to the 18 compared to the 17?