Jon, here is what I have been able to find out about Micro Switch Corp. I think they are still in business making many different micro switches. Micro Switch is a Manufacturing company, Tel is 815-235-5500, at 11 West Spring St, Freeport, Illinois. I will contact them tomorrow to see if they can give me any indication of what that unit might have been used on. I suspect not, but I will see.
Is that unit attached to the contraption that is attached to the valve cover? It looks like it might be attached to something. Have you been able to find ANY indication of who manufactured that contraption attached to the valve cover? If you have not done so, go over that thing with a fine tooth comb and see if you can find any model number or manufacturing name on it. Someone had to build that thing, and I hope it was not just something that some previous owner put together from a bunch of parts. I am headed to bed, and I will let you know if I make any headway on this later today. Thanks for the additional pix.