My new screen arrived today. The FM camera fit K2 type just needs the dremel on it to remove the tab, which is in the wrong place for the D1 series cameras.
....I've also bought a s/h F6 screen online "just to see"....and yes, I should have believed the helpful guy at Ffordes when I spoke with him!. The screen is about half a mm too large in width depth and thickness...quite a large unit, even for a full frame viewfinder..Pretty exsensive dremel work to modify, even if I were to attempt it (I'm not going there)
So, I now have a screen for a Nikon F6 which will probably go on the sales page!

oh well...I had to find out the hard way! LOL