Just run away, I don't see the need of killing all the cops. You keep complaining about the S.W.A.T van running you over when you stand in the middle of the road expecting them to just stop the van, get out and try and shoot you. You say this because you know that if they did do this you would be able to kill them almost instantly. And so you want this to be the case.
What I'm trying to say is the S.W.A.T van ain't supposed to mean fresh meat it's supposed to mean get the fuck out. Every time I try to take on the S.W.A.T van I die, You know why? because it's like trying to punch a Lion, I would have a better chance of surviving by running rather than running up to it and trying to kill it. So I have learned that when the S.W.A.T van shows up it's time to go.