BMW R75/5 Airhead, Part #1 Basket case restoration.

I found this old BMW R75/5 in a cold damp garage. It has been sitting in this garage many years. I have no good history and no knowledge of why it has been partly disassembled. This is the start of this project and i have not yet decided what to do, or what direction to take this BMW airhead project. This could turn into a money pit.