Tank's INC Vent/Rollover Valve

Just to clarify, I'm not venting the tank into the trunk.
There is a vent for the factory fill tube, it runs from the top of the vent tube through the vent tube trunk floor gasket to the outside.
Iirc, mine has a short soft line into a hard line loop, then a soft line out.
I tapped into the short soft line.

Without photos it's difficult to figure what you are doing/ done.