iFixit has their iPhone safely disassembled, complete with parts identification and photos that will help you through the process.
Why disassemble your iPhone? DIY repairs such as changing the battery immediately come to mind. As nice as Lithium Polymer cells are, my own experience is that they tend to die and not hold a charge after a couple of years. From the photos, it looks like a relatively straightforward soldering job to replace the iPhone’s massive battery.