Eddie Hazel comes to mind and some of the material from P-Funk/Parliament. It's just not stuff that would have been heard on the radio.
Fishbone, Eddie Hazel, and a lot of stuff that would have been considered Acid-rock or funk with a heavy flavor was long gone by the time In Living Color hit MTV. Fishbone was still out there performing so it was a little easier for people to make the connection.
YouTube didn't exist so performances from The Midnight Special, Don Kirschner's Rock Concert, or The Mothership Connection laying down "Cosmic Slop" in Houston would have never been seen by the general public.
Even Hendrix got his start with Little Richard and recorded on an Isley Brothers song before being "discovered". He couldn't exercise total musical freedom in America until the time in England.
Another overlooked musician is Buddy Guy. You can't listen to his older solo stuff without hearing how liberally Jeff Beck borrowed.
