Wow! This is great stuff! I was able to get my hands on an E-body 3-speed wiper switch and a harness out of a 3-speed wiper car that I can rob the plug off of. Now off to buy a lottery ticket!

So if I am reading this right, all I have to do is remove the spade connectors from the two plugs from my 2-speed harness and re-insert in the one-piece (3-speed) plug using the diagram in the link? Is that correct?