> What should I be using for sanding- by hand, a
> palm sander? Also what kind of sandpaper?

Where the panels come together at an angle I would think you'd not want to sand with a machine; it's too easy to be too aggressive and end up cutting into the plywood more than you want.

I do this step all by hand. First I use a small convex sureform tool (Stanley or Sears) to get the big lumpy stuff off, then 80 or 100 grit dry paper on a rubber sanding block. You can use the depth of the topmost layer of the ply, usually 1mm thick, to create a bit of rounding across the seam so that the glass will lay down better.

Where the panels meet more flatly, say up near the bow, just remove the lump and hand sand down to the surface. You won't need to cut into the wood much, if at all. You don't need a perfectly smooth glassy surface at this point, just pretty smooth. The glass & epoxy added on top will fill small imperfections.

> Regarding epoxy, I am using gloves whenever mixing and applying, but what
> about when pulling wires? The epoxy is hard but still "green"
> (at least I think so.) At what point is it no longer necesaary to be using
> gloves? Thanks.

I dispense with the gloves when the epoxy no longer sticks to me, so removing the stitches without gloves should be okay as you need to wait for the epoxy to harden first anyway. A bit of tackiness says the epoxy is still green, and usually it will accept shaping with a sureform or knife at this point but will resist (by clogging) sanding. At a later step, this is when you want to trim extra or overhanging glass.