Easiest way to do it solo is to go gung-ho in Battle Dress. Get out your machine gun and sneak around to the back of the tank by going through the warehouse. Don't let them see you until you're ready to strike! Then take aim at the red barrels on the back of the tank. Blow one of them up and the tank will be unable to move for a while. That's your chance to unload your stock of grenades on it while it can't move. After a while it will start moving again, so get out the machine gun and try to destroy the other barrel, but it'll be tougher since the tank will likely be driving around now. Unload any grenades you have left if you didn't get them all out the first time. Using the RPG, it's way easier to take potshots at the tank even if it isn't stunned, so save those for last. After you run out of all that ammo, shower the thing with the last of your machine gun ammo and it should finish it off, but you can find more ammo around the map if you run out.
Don't worry about the infantry escort, your Battle Dress should be plenty to absorb most of the trouble they give you, but you can always pop a ration or two if you run into trouble. Don't worry about trying to kill the commander, either. You can destroy the tank itself if you have the right equipment, and he won't even pop out until you take out 16 dudes escorting him, so by then you'd likely have to scour the map for new ammo which is just annoying.
It's also possible to stealth kill the tank if you have a lot of patience or a well coordinated group of people to play with, isn't that right, bernardobri?