Not sure here, but wasn't Big still recovering from the Lions incident when Indy took place in 1970? Maybe the picture is from '69?
Never mind, I already found my answer. Garlits lost in the 3rd round to eventual runnerup Nicoll. The Big Go marked his return to competition.
Didn't Big make his return in the rear engine car?
My guess is that the Lions incident is maybe 6 to 9 months in the future. But, that does look like the car Big Daddy sawed in half at Lions.
-90% Jimmy