when they say "47" in that context they mean 47 2nd series, as in the Advance Design model, not 47 1st series which is in fact just a '46 sold late .... there may be a few 47 AD parts that'd fit on a 46, but not a lot and usually the catalogs will show the range of years parts fit .... take a look in the gallery to see the break points in the different model years
Bill