An easier way to remove the front and rear lens assemble from a Hasselblad 500c Carl Zeiss Planar 80mm lens. Spanner wrenches did not work well in my case, so I create this tool to help loosen the front and rear lens assemble. You will need to cut a piece of metal measuring 46mm x 3mm x 1mm (front) or 43mm x 3mm x 1mm (rear) using a hacksaw. I cut it from an 18-gauge steel rafter tie that I purchased from Lowes. Then insert it into the printed part and glue it in place. In some cases you may need to add a drop of acetone to loosen up the threads. 

Please consider the risks involved before attempting. You may need to seek professional help. I cannot be responsible for damage to your very expensive camera.