Dennis Wilson of the Beach Boys was the one who referred Manson to Terry to make a record. Terry had the good sense to turn down Manson. However, his guardian angel must have had to work overtime. There was also some evidence to believe that Sharon Tate was the intended victim. Hard to tell for sure with Satanic murders what the true motive is... Certainly cost some precious lives... which still has a haunting effect 44 years later. I was a kid at the time and remember it in the news. There were also the related LaBianca murders that followed 2-days later. All very sad and tragic.
Another group Terry produced... Mark Lindsey's Band... Paul Revere and The Raiders. I used to watch their TV program after school. They lived at the "infamous house" before Terry Melcher and Candice Bergman, and the Polanski's - Roman & Sharon (Tate.)