I recently picked up a clean Konica IIIa with the 50mm f/1.8 lens. I'll be getting it CLA'd but first I need a lens cap. I'd almost prefer a push-on instead of a clip-in just to avoid any possibility of touching the clean lens. My ruler says that a push-on would be either 58, 59, or 60mm. A clip-in would be a bit less. Can anyone confirm the correct size, of either type? I'd certainly appreciate it.