You need a release tool that unlocks a white plastic connector down at the slave cylinder down on the transmission. the line comes with a new master cylinder. You might check to see if a GMC or Chevrolet dealer might have this tool. It's a Kent-Moore tool # J-36221
Hope this helps.
That is incorrect chevys do not have that type of clutch line all you need is a small pick similar to a small nail there is a small round clip you tap it out a little then pull it out with a pair of pliers