On ours it's listed on the build sheet (we factory ordered), in the owners manual and also on a sticker on one of the cabinet doors over the sink. Model numbers as well as serial numbers are all there.
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft
Charter Good Sam Lifetime Member, FMCA, SKP
RV'ing since 1957, NRA Benefactor Life, towing '05 Odyssey