I just sanded my hatch covers and am ready to start sanding the rest of the boat. I'm using a random-orbital sander. When I sanded the hatch covers I noticed that I started cutting through to the glass before all the shiny patches were gone. The fabric must not be completely flat on the panels.

Should I stop sanding with the random-orbital sander and finish the remaining shiny parts by hand (the surface won't be flat and won't look as good when varnished), or should I just go ahead and sand down the fabric in the areas where it is high?

If I sand down to the fabric in a few areas, will the varnish cover it up?