FYI- I hijacked my first armored truck tonight. You can get the money from them, you just have to drive it until it blows up. Or I suppose if you have a grenade launcher that might work too. The truck is so tough though it died on me long before the point it would blow. Luckily a dump truck was happening by, so I got into that rammed and it a few times til it finally blew up and spewed money everywhere. Jackpot! Now, time to find that ice cream truck...