My 1984D. When I first read "The Cherrrypickers Guide" I fell in love with this variety. When I found it roll hunting it was covered in black corrosion, like the NW spot. I thought I saw something with IGWT so I soaked it in mineral oil. after a few weeks a lot came off and I knew it was the one coin I wanted the most! It was ruined though. The date was completely covered by black crud and you couldn't tell if the 9 was doubled or had a big PMD gouge. I ruined it further by cleaning it with soft brushes, mineral oil soaking, and xylene rinses. That was the only thing I could do if I wanted to actually see the date. I am very happy with the way it turned out.
Sorry it took so long to answer....... I had that coin for a long time and have no idea where I got it. I decided to send it to ANACS when they were doing a special this year PS Happy New Year