The screen now faintly has steady lines at the top and bottom each approximately 4 (or6) pixels from the edge. There are also grid-like cones within this short screen border at top and bottom. Seven narrow points and wider ones between. And the screen flickers faintly and only intermittently with pale lines across it's main body, showing a six by four grid. Is this the "grey raster?"

I hear read activity in the drive.

The sliders are indeed hard left.

I do not, however, have a boot Disk Tools floppy. Perhaps I'll go look for such. . .