I'm getting conflicting info. Can somebody tell me if a 1 piece (lowrider style) 2 up seat from a 2010 sportster will fit a 2006 sportster?

2006 and 2010 Sportsters are both the newer rubber mount style frame, so I would have thought seats are compatible.  But from what I remember Sportster seats are made to fit different tanks.  So a seat made to fit a 4.5gal tank won't fit a seat made to fit a 3.3gal tank.  Check the part number on the seat, the manufacturers usually tell you what models it will fit.