Before we start, EOS-Holga mod posted on Litratista.org EOS-Holga mod posted on Litratista.org, and aTanguay's Nikon-Holga mod posted on flickraTanguay's Nikon-Holga mod posted on flickr are two must-reads. I started thinking "Hmm... what if" after reading their posts and came up the idea for my little project! However, they mounted their Holga on DSLR bodies which you can see the focus. On uncoupled rangefinders, you'll have to eyeball the focusing distance and set correct foucsing (or little 'flower' icon for near, 'person' for mid, and 'mountain' for far). All of this will be academic if I can build a lens that will have the correct focal length (60mm) to be in focus at infinite.
Drawing diagrams and reading math textbooks won't help, so I'm just going to build one and see how it goes. After pounding two cans of Red Bull, I am saying "Let's do this"!!!