In preparation for calibrating the pitot system, I discovered that there was a leak in the system. After some diagnosis, I determined that the leak was inside the wing. After removing the wing inboard connection and finding no issues, the wing was pulled, flipped over, and the inspection panel behind the pitot tube was removed.
No issues were found until all the fittings were removed, and the plastic tube running between the pitot tube and the wing inboard connection was tested by itself. It leaked! There was a small leak just behind where the pitot fitting had been. I apparently damaged it while assembling the system many months ago. About one inch was cut off the end of the tube, and the system reassembled. Retesting revealed no leaks, so I moved on to calibrating the system.
Since I had proven that the pitot system through the wing including the wing/fuselage connection was leak free; the manometer was connected to the system at the side of the fuselage using the same kind of connector mounted at the inboard end of the wing.
While pressurizing the system and recording the pressure indicated by the manometer at each measurement point, I was amazed at how closely the ASI and the EFIS indications tracked each other. The difference between the two was never more than 2-mph over the entire range.
I still need to compare the monometer readings to the cockpit readings to verify the accuracy of the pressure conversion.