Just completed the Framing Frame job on Overkill and stealthed the last mission. It took three hours. I felt sick near the end because I was so nervous something would go wrong...
HOW
Seriously!
I spent way too long just trying to stealth the first part, stealing the art. What's the trick with it? Did you do it solo?
It's a rough trip. I actually just did it again this morning and got just under $1 million, and somehow we managed it on the first try. Even more boggling, I was the only one with a mic and one of our guys didn't speak English. So it's very possible, as long as everyone knows what they're doing.
The first level is easy: Get someone with shape charges or ECM hacking and blow the security door if you can't stealth it. Stealthing mostly consists of splitting up and trying to grab all of the paintings before the alarm's sounded, and then running the roof to get the paintings to the car. If you can't stealth it, you really need someone that can bypass that security door. Get all of the paintings though. The last level is hard enough as it is without them.
The second level is even easier. Once you get the guy four paintings, the back door will open and you can start moving money. Just move it as far as possible, crap only hits the fan once you've handed off the last painting. Someone with the throwing skill will be useful here to move the money over obstacles for a quicker getaway.
The final level is where it sucks. You need someone with both Dominator and Smooth Talker. Intimidate all the guards you can and kill those that don't get intimidated. Once the guards are out of the way, the biggest problem is the cameras. You can't destroy too many or the alarm will go off. Everyone who has it should bring an ECM jammer. One person stays on the camera at all time to spot guards and find the electronics.
You mostly have to be really lucky. Once you open the vault you're good, as long as a stray guard or camera doesn't spot you.