Never heard of Ken Johnston till now John. I presume Mike Urso left soon after Grand Slam? KJ must have been there long enough to have got himself on an agency promo photo. He crops up on another act on that same web site http://home.socal.rr.com/jcentral/chris.htm
I also found a forum about the Atlanta Pop Festival of 1970 which has several references to Rare Earth playing their 30 minute version of Get Ready. If you were there you might enjoy reading this. Hells Angels pushing people around who were just trying to avoid being struck by lightning in the field. Wow!
Hi - my name is Ken Johnston and I played bass for Rare Earth from June, 1979 until June 1981. Mike Urso was under contract with Capitol Records while the band was in court fighting over the ownership of the name Rare Earth. When the smoke cleared Gil Bridges had won that battle. I auditioned among over 100 bass players (according to Peter Rivera, the drummer) and won the position. More if you need it at kjohnst2@gmail.com.