The Gretz pitot mast came pre-drilled with holes to mount the pitot tube. These holes were big enough for #8 screws. I read the Dynon instructions for installing the screws with the caution on not drilling too deep. Set up a clamping rig to drill on the bench and used a drill stop to make initial hole to approximate depth. This was too shallow and the drill did not go all the way through the mounting area in the pitot tube. Gradually increased depth until I just broke through to the spongy filler material inside the pitot tube. Cleaned out the hole as best as I could and tapped hole using Boelube on the tap. Bought stainless steel screws and cut them down to fit. Installed first screw, then repeated process for the other three screws.
Plan to use old fuel tank sealant (expired 4 years) to mount the static ports, so I mixed up a batch to see how it would do. Smelled just as bad as I remembered, but components mixed well and set up in a normal amount of time.
