I like a lot the dirty ice stealth on overkill, but it's almost impossible to get all the loot on the front store then unlock the basement to call the manager in time to unlock the jewlery machine, could be a way to do a mod that makes the manager never leave the store? so you can call the phone in the office to lure her to open the machine door? I was able one time to do it with fixed RNG, by knowing the basement code it is doable, but if you want to do the heist the way it was designed, I wasn't able to find a way to get there in time.