Bickle, this mission is rather difficult without cheats so if you are impatient, feel free to use cheats. There should be body armor in the warehouse. And I highly suggest you crouch and take cover. When you get outside take cover behind the cop car and take out any nearby cops when possible. This is a leap of faith but run to the car(hope you make it) and simply drive off until you lose the wanted level.
Is there a full moon out tonight Bickle? Are you and Nascar in cahoots for asking weird and bazaar questions? I have no clue as to the answer of your question and it sounds like zexion is on to you also. ♥
Bick, sorry I can't help you. I burned out on the role playing games a long time ago. Actually it was all the crap you had to go through to get into playing the game. Doom is where it ended for me.
I will have to seek higher guidance from my 10 year old grandson to answer that one. He whizzes through those things. When my husband or I try to do it we have post it notes and diagrams all over the study and still are calling all the kids for cheat clues.