iPhone 4s hardware in the body of a 4?

Here is my situation. I'm currently using my iPhone 4s. It is, for the most part, fairly functional but has a few issues & home button is missing. I was recently given an iPhone 4 that is in perfect cosmetic condition due to spending its entire existence in a life case , however it can not be updated any further & therefore many of my apps can not be installed on the it. My question is this, is it possible to switch all the inner hardwear of the 4s to the body of the 4? Looking at them from the outside they seem identical but I've never opened them up to see what's inside. I'm just curious if this is even something that can be done? Thanx