My truck was also built in the Janesville plant and is the same year as yours. I thought the production sequence number, which is the last 6 digits of your VIN, was the number of trucks altogether produced up to when your vehicle was built. GM didn't separate how many trucks were built versus Blazers and Suburbans. They were all roped in together in one lump sum. I believe even S-10's and small Blazers are factored into that total. For example, the last six digits in my VIN are 155737. So that means there were at least that many trucks including mine produced that year.