This subject has come up many times, that maybe the reason nobody responded. Normally we would say do a search, but the search function is down right now, so....I for one canned the evaporator tank, and welded up all the vent lines on the tank, except the one above the sender. From there I ran a fuel hose to the spot on the fuel neck that used to attach to the evaporater tank. This is now my one and only vent hose. I drilled two small holes in the fuel cap to help the tank vent. This works very well, with no problems in filling the tank.
As for the charcoal filter I canned that too, but since you live in California you may need to keep that.