Well, I found the screws to remove the top gear box and ended up cleaning up and replacing with new grease.
I was afraid of losing the screws. I found a neat YouTube on how to magnetize screwdrivers. So simple. Just slide your screwdriver shank over strong magnet ( I used the bottom of my magnetic parts holder cup from harbor freight) from handle to tip multiple times and also rotate for multiple time until you get it all.
Finished cleaning up the underside.
Tomorrow I’ll replace the feed dog. It is pretty messed up. I received one from diamondneedle.com, but it is not an original. Does not look as nice as OEM.
I may just order an OEM. Only place I found was below
NC-6 is Seiko model that is same as earlier 206RB-4.
If you go to that machine, you can scroll to the part.
Then rewatch the 4 hours of maintenance videos and start tackling them.
No one ever accused me of being quick.