Next I drilled the pitot tube attach holes using the staff as a guide. These are tapped for number 6 screws so I think I used a #36 drill bit.
Round head screws look dumb so I countersunk the staff to use flush screws. I bought some stainless 6X32 screws from Aircraft Spruce. Spruce use USPS for shipping which saves a lot when shipping small hardware parts.