You will need a 13 mm wrench.
To loosen the pipe nuts, use special wrenches for brake pipes, since the nuts are very tight and usually corroded, as a result of which, when using ordinary wrenches, the edges of the nuts are crushed.
Note: The work is shown on the example of the pipeline connecting the ABS hydroelectronic unit with the hose attached to the working cylinder of the brake mechanism of the right rear wheel. The other pipelines are removed almost in the same way, the only difference is in the places of fastening of their holders on the body.
1. Drain the brake fluid
2. Unscrew the nut securing the pipeline to the ABS hydraulic electronic unit, which goes to the brake hose connected to the left front wheel brake master cylinder (for clarity, shown with the master brake cylinder removed).
3. Unscrew the pipeline holder mounting bolt and remove the holder. Remove the pipes from the plastic holder socket in the front part of the body base.
4. Remove the pipeline from the holders on the body base (Fig. 9.8) and remove it.
Fig. 9.8. Location of brake pipe holders on the body base
5. Unscrew the nut securing the pipeline to the hose connected to the brake master cylinder of the right rear wheel...
6. ...and remove the pipeline.
7. Install the new pipe in the reverse order of removal.
8. After replacing the line, bleed the air from the brake system (see "Replacing brake fluid").
(The material was created based on information from the website: CHEVYMAN.RU)