16900MBG003 has straight inlet and outlet. I think 013 has a U shaped inlet. I appear to have 003 on my 99 FiX, but the parts fiche at a UK supplier (Fowlers) shows a picture of filter with straight inlets and part number 013 - so highly confusing.
In a Youtube video of someone changing filter on a 2000 model, the filter appears to be 013 with the U shaped inlet. It may be possible to fit that to an earlier bike, but the rubber pipe which joins from the pump outlet to the filter inlet would need to be modified (see my reply below for an update on this).
I know this is an old thread - but this may help someone finding the info. by Googling - as I did.