In the event, after using the bradawl (pointy thing for making pilot holes in wood) as a guide I simply fixed the conduit clips with self-tapping screws.
Yes, I hear what you're saying: "Maybe good enough for Boeing, but not for my aircraft".
And so yes, you can fix the clips to the laterals using countersunk M4 nuts and bolts, should you so wish.
Here then is a picture of the laterals in place once clipped to the chair.
