Don Williams (those Williams boys still mean alot to me, Hank and Tennessee) was a We 5 or Pozo Seco (I always get those two mixed up)

Jim Messina of Loggins and, was in The last version of Buffalo Springfield.

The Stone Ponies was early Linda Ronstadt

Emmylou Harris was the duet with Gram Parsons before being better known as solo self.

Vince Gill was a Pure Prarie Leaguer bander in their later configuration.