Fabricate fuel tank vent lines from 5052 aluminum tube.
A small change was made. Instead of a bare, unprotected vent line protruding through the bottom fairing, I opted for an aftermarket machined aerodynamic aluminum vent. The same vent is used on the ER tanks. The change required a shorter length of tubing, flared for the AN fitting that attaches to the aluminum vent through the fairing.