Question About MITM Attack.

have a question about MITM attack (or Whatever This attack is Called).

Let's say i am connected to a Router and three more users are connected to it, router address is 192.168.0.1. Now i don't know the Login Credentials of the Router , so i use Ettercap and Some DNS poisoning etc Stuff and i do attack on an User "A" , now whenever User "A" type www.google.com it auto redirects to original Router Page whose address is 192.168.0.1 , now User type it's Login User and Pass (Because Router Page Not Using HTTPS so it's easy to Read data in PlainText) , now i am using Wireshark to read all Trafic and Filter all Requests related to 192.168.0.1 and i get the user name and Pass.

So is this Possible ?? if yes Then How i do it ?? if NO then Why ??

Thanks in advance.. :)