Fantastic, congratulations. For 25 years, I used a slightly later M3 which I had a technician convert to single stroke. Mine had the geometric progression of shutter speeds. Does yours have the glass pressure plate? If so, be a bit cautious with static marks in extra dry conditions - wind the film slowly. Also, if you want a 35mm lens, the ideal way is one of the RF units with the attached goggle eyes. These convert the frame bars in the viewfinder for the 50mm lens to show the coverage of the 35mm lens. Most of the RF lenses are now probably collector items = expensive. Have fun.