I only posted the chart because of the S2 meaning possibly being something other than what AMK listed them as. I didn't think they where something other than what I ordered, but I never say never to anything
I like everything we are all adding to this thread. Lots of good info.
Seeing palmetto is no longer an option, I see there are phosphate kits on ebay that are calling their product black phosphate. not sure how its better than manganese, unless they are adding something to it?
Were our cars originally supplied with black oxide? I used to think so but was reading somewhere that they where in fact manganese. But, that was on a ford website. While I think I have a plan of attack now, I still enjoy learning more about anything car related.
We used to use cheap black oxide self tapping ground screws at a shop I worked at in the early 90's. those things would rust so fast, they might have well had been bare steel