Sir: and yet more potentially confusing "fuel pump info" that needs clarification:
1-whether a Buell XB is an S....R...or any of the "long frame" variants such as Stt, X,XT....makes no difference re. the pump.
2-IN YOUR PICTURE the pump on the LEFT is early style pump....factory part # P0130.5A8----SUFFIX B4U.
IN YOUR PICTURE the pump on the RIGHT is later style pump....factory part # P0130.5AA----NO SUFFIX
3-they DO interchange but there is a slight difference in the wiring plug that must be addressed. pump pressure for ALL 2003-2009 pumps the same....2010 regulator and pressure different.
attached is pic of new unboxed pump i pulled out of inventory to show you EXACTLY what the 2008-2009 OEM NEW pump looks like.
Attachment 10887