I am seeking information on my g-grandfather, Michael F. McKenna, and his brother, Thomas D. McKenna, who mined at Goodyears Bar aroung 1852-1853, filed a quartz claim (location undisclosed) in Downieville in June 1856 and and ran a store in Goodyears Bar or in Grass Valley in the late 50s before moving to San Francisco.

Any help would be appreciated