Yup the 67’s and the 69’s, I think are the best.
And i get a better feel for the clutch when I don’t wear any shoe on my left foot.
I always wore shoes and developed intuitive feel for my clutches - had a Schaeffler revloc clutch in a ‘69 Firebird I built and the pedal pressure was enough that lack of shoe would have made it uncomfortable.
I had a friend who preferred no shoes at all when racing but I didn’t have that much “Hillbilly” in me