My 73 H2 was built in 6/72. I just saw a 72 on ebay that was also built in 6/72 and the engine # was just a couple hundred less than mine. I think the difference was just the paint and 73´s had a chrome front fender. The real change was on the 74 model. They had 3 hp less and used a different oil injection system and a longer wheel base.