Cell phones falling into water are comically common and disturbing at the same time. It needs some quick action as well as damage control. In order to salvage the situation, there are a few things that you can do. Get it out of water quickly and dismantle all parts. The SIM card should be saved first as it contains all data. The device should be put into absorbing towels and dried off.
When it comes to the First and Second generation of the iPhone, you have to first take out the SIM tray with a small paperclip. Then remove the screws on both sides of the charging spot and take off the back cover using a little force. Detach the ribbon cable that connects the case to the motherboard and remove the display panel using a spudger. The motherboard had to removed after you have located and removed about 8 screws and a “4” ribbon cable.