How do you beat the boss of Memories of a Lost City, Chapter 4?

This will a short one to do but I will tell you the drill, to defeat this chapter is very easy. While facing first the zombies, simple headshot BOOM!. Next lickers, aim at their mouths. Third medium size black tigers (spiders), shoot their eyes (located on top of their fangs). Now for the boss fight William Birkin G2, this was one was a pain in the ass for me first time but I beaten him and the game 20x, so aim at the shoulder eye, when the dodge sequence arrives, do it fast, now when he is swinging wildly shoot him trigger-happy with the submachine gun all you want and another dodge sequence comes up, while on the platform shoot him in the head, he grabs you trigger-happy his ass with the submachine gun,nowfor the annoying part that you known so while hanging on the ledge, shoot the pipe on the top to destroy it fast and stun-kill William and dodge sequence comes up stun-kill him and it's over.