I recently found this example that had spent much of the past decades in a barn. And look at that chinstrap modification! I have been looking for a MkIII model for some time and decided to bring this home. I plan on cleaning it up a bit and using it in my classroom display this year.
My thoughts on restoration are to remove the screw and liner, then scrub both liner and shell with soap and water to get rid of the dirt and debris. Would it be worth looking for a new liner/pad? I would like to add a net to cover some of the rust, and perhaps a new chinstrap. I would love to hear any input on this process!