Yes you can pull wheelies in 2nd gear. And yes you can do them in 3rd on a stock bike. I'm going to show a link to badweb if this is allowed if not I'm sorry???
http://www.badweatherbikers.com/buell/messages/32777/289619.html
http://www.badweatherbikers.com/buell/messages/32777/214853.html
http://www.badweatherbikers.com/buell/messages/32777/289619.html
http://www.badweatherbikers.com/buell/messages/32777/214853.html