Some aeroplanes (such as the Chipmunk) don't have a lean cut off
SSD,
I was surprised to read that. The T10s I flew in the 60s had a "slow-running cutout", consisting of a ring and a cable on the right side of the cockpit. I had to look up the Pilot's Notes to double-check my memory and I see that it was introduced as Mod H246. Originally T10s were shut down by turning off the ignition switches.
Further reading shows that the RCAF Chipmunks also had a slow-running cutout, but the Canadian civil ones did not.
Was the cut out removed when the T10s were placed on the civil register?