Samsung Galaxy S has water damage was working now won't turn on

My phone got soaked I put it in rice for 48hrs. It worked at first only problem was the power button wouldn't work properly. It was sketchy sometimes I could phone to sleep other times it would have a pop up like I wanted to shut it down or put it in plane mode. Then it froze I took out the battery put it back in and now it won't start up at all. If I plug it in it shows it's charging but thats all. I tried to figure out how to take off the inner case but after I removed the 6 screws I can't figure out how to open it. I know the battery now needs replacing but I need to see what else it needs. Please help!!!!