vehicles imported by PW or RT for conversion are not dutiable for vehicles returning to th eUS after conversion- this is all figured out in advanced and the vin assigned to show the destination market ( ie CA or US).
they will pay which ever duty on vehicles which will remain in CA -
all this stuff is so complicated it makes your head spin.
I know that DRL's are one aspect and that is how they deal with it on that one model- some other models may need the ecm re-programed--- or others like my 2013 Prius V doesn;t even have the DRL's...just depressions in the bumper shroud where they should be ( and i am pissed at toyota about this- the brochure says DRL's on my model...)
On my PW a coupleo f the US market changes are labeling to mark the rear seats as "not for use.." and also the latches on the rear windows are secured shut...well, they were.
Mike