https://youtu.be/gNWWoNDpmDE The removal of the clutch shuttle valve (clutch accumulator) is required when installing a twin disc style clutch to gain more travel in the hydraulic system. I run a Competition Clutch Stage 3 dual friction clutch in my 2013 4x4 Tacoma and even with all the play taken out of the clutch pedal i had a difficult time getting it into 1st gear at a stop. This solved the problem. It also made the clutch a little bit easier to depress and gave it better feel. Notes: -I clamped the fluid hose at the clutch master with clamping pliers to keep the master from draining. Bleeding was super fast too. -I accessed the upper shuttle valve bolt through the fender well with a long extension, shallow 12mm socket attached to a universal joint. -The fitting to join the two hydraulic lines is metric thread available at a local parts store.