Mike,
AFAIK, the 3U box only has a taller 2nd thru 5th gear ratios, with the R&P ratio remaining the same (3.89:1). The 016 suffers from a low ratio 1st (3.60:1), relegating it nearly useless (It's worse in the 5N). Still, the 3U is a better option.
Euro recyclers tend not to separate...