While it's on the right side downtube, mine is more easily viewed from the left side. My 07 1200R was built in July of 2006. I bought it from Chicago Harley in June of 2007. I was somewhat concerned that it sat idle for so long, but haven't had any problems yet, knock wood.
I got a leather diploma type thing with all the build info on it.It says when the motor was made and when the bike was assembled.I don't know if they still give those when you buy a new Sportster or maybe the just did it for the 100th anniversary bikes. I actually have it on top of my TV