Martyn
Supporting Sponsor, Overland Certified OC0018
So just to make sure I can drive thru California on my way to Baja and I will not get stop because of my gas can carriers?
You should be fine. Remember the NATO can is compliant, the regular spout is the issue. If you want to be compliant buy a CARB spout for your NATO cans.
Ownership of older or non-compliant cans is not the issue. You just won't be able to buy non compliant cans from a vendor, the thought being the older cans will be taken out of the system due to age. It's the same as if you were driving an older car that originally didn't have seat belts, you wouldn't get a ticket.