Where is the time going?

Winter is a great time to do maintenance on the bike. I need to bleed the brakes and clutch and change the anitfreeze. Brakes/Clutch should be fairly easy (he says with hesitation in his voice), but the antifreeze seems like it might be a bit more challenging. Apparently, I will need to either remove or at least slide the gas tank backwards on the bike. Like most things, the first time will be the most difficult, but it needs done. "They" say every two years, and it has the original still in it after 4 years.