Installed and working well Recommend replacing the master cylinder. This black substance in your fluid is due to the rubber seals scraping the hole and grinding it into fine particles that disperse throughout the system. Flush it out with new fluid and you're still paying less for a job well done than if a mechanic installed just that part. Simply order a Haynes or Chiltons manual for your vehicle if you need step-by-step instructions. But hey, it's 2019, Google exists.