Muleskinner (w/Peter Rowan, David Grisman, Richard Greene, and Bill Keith) is a career highlight for all of the above. Bluegrass, newgrass, country, country-rock with Clarence playing stellar acoustic + electric.Recorded 1973, shortly before his death.
The New Kentucky Colonels (the White Brothers) Live in Sweden. Good luck finding a copy. Also recorded in 1973.
All of the Byrds albums from 1968-1971 feature his guitar work. They can be found easily and cheap in used record + cd stores.