I have a 4x5 speed graphic with the pictured lens and shutter. It is a 152mm f4.5 Ektar in a Graphic shutter. What are my options to send the shutter off for a cleaning as the slower speeds are running slow. Also I have a 127mm f4.7 in a Graphex shutter that is 100% functioning. It does not appear I can swap out the lenses to use the functioning shutter with the 152mm lens. Also, with the 152mm lens and shutter, what are my flash options. I see the bi-post flash sync however, there is no setting for bulb or electronic. Can I use it for electronic flash? Any help greatly appreciated.