First off – you're referring to clang 1.0 based on LLVM 2.6. There is no clang 2.6, only a clang 1.0 based on LLVM 2.6. The clang issued with LLVM 2.6 is the same as the one with Xcode 3.2. (see Wikipedia : "On October 23, 2009 Clang 1.0 was released along with LLVM 2.6 for the first time"; I also know this from personal experience).
So, don't overwrite! Rename them to their respective version (e.g. Clang-1.0), then create a symbolic link to the one you want. If something goes wrong, you can switch it to the original version.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.