Thanks to this thread I finally updated two of my machines. I didn't have a Eprom programmer, so I didn't wipe the chips before install. Seems to work fine, no settings lost.
On my NGG, after removing the battery holder I did notice some damage I didn't see before. One trace seems to have exposed copper, and a little bit of green on the solder point. Anything to worry about, or just leave it alone?20170310_201811 (resized).jpg