It took me ages to figure out the 3/2 you mention.
I have the arrows/f2 bases and really don't like being rigged with tack pulleys. Even when rigged like this it seems odd.
With 4 pulleys I can see no option but to change to a different type of base with the pulleys alligned in the same aspect.
I think the current extension from most of the manufacturers are useless for this type of system when the pulleys are alligned with the sail. If the pulleys were alligned 90degrees to the sail this would be much better.