That's Stirling Moss talking to Tommy Ivo in the 2nd Pic. I'm sure it's him as there's also a couple of pics of him at the Dragfests in the Jan '65 Super Stock and Drag Illustrated Magazine.
I havn't heard he drove but I seem to remember that Dennis Jenkinson of Motor Sport who was his co driver in the Mille Millia {?} ran a bike at the drag fest so it's quite likely that Stirling was there. By 1964 he had retired from F1 but would have been fully recovered from the last accident.