leica screw mount

After messing around with some non-Leica lenses, I though I'd try to shoot my Leica lenses with a tripod at the same target. I had to dismount and remount the body because the lens selection was inadvertently left in a manual mode incorrectly set in a couple of cases. Also, all the lenses were...

Hello, I have a wartime CZJ Sonnar 5cm f1,5 in Leica Thread Mount serial # 2870001 which seems to date it approx. from 1942. I need advice on how to unscrew the optic module to check for matching serial numbers and perhaps determine it's authenticity. I am loathe to dismantle/damage the lens due...