[High Sierra]

That’s definitely a California model, as I have the same setup. I get the “vapor lock” on mine from time to time, and would love to add that new ball valve, but I don’t know if it will cause any problems with the emission system.

No issues by changing out to the rollover vent. And it should be done on all models regardless of cali or not. Most times the change out will fix the fuel gauge error reading.