pretty easy to pull off, without many incredibly fiddly timing NPC route stuff if you wanna do it from the tower like i did, bring a lockpick you don't need to start as stage crew but it speeds things up a bit main things are to get the fireworks remote, go downstairs to shoot the security footage computer, and get your sniper rifle to a position to shoot both targets within 10 seconds of each other, tower just happens to be really good for that