Thanks, Dennis, for your interest and help. I know a little bit about circuits and hardware from a decade of tinkering, but I have no textbook training. Basically, every time something goes on one of my old machines, I learn something new about electronics. 
I did use a pair of working headphones and checked all the combinations you list. When I have time I'll see if I have some donor headphones I can cut. However, the fact that none of the headphone jack pins conduct to each other means that the sound should work without the port installed at all, right?
Living in Orlando, I am fortunate to have Skycraft (http://www.skycraftsurplus.com/) nearby. Now that I have a shopping list (caps, headphones, and maybe a 3.5 mm mono TS jack/port), it's worth a drive over.
I did the washing last night...we shall see how it went after another day or two. I can still see come corrosion on the FPU socket, albeit less than before.
I did use a pair of working headphones and checked all the combinations you list. When I have time I'll see if I have some donor headphones I can cut. However, the fact that none of the headphone jack pins conduct to each other means that the sound should work without the port installed at all, right?
Living in Orlando, I am fortunate to have Skycraft (http://www.skycraftsurplus.com/) nearby. Now that I have a shopping list (caps, headphones, and maybe a 3.5 mm mono TS jack/port), it's worth a drive over.
I did the washing last night...we shall see how it went after another day or two. I can still see come corrosion on the FPU socket, albeit less than before.