Help, I started the repairs to hatch covers

I cut the skin of the underside of the floor hatch covers (1985 CC- fish box and other floor hatches). *

I knew the wood was rotted, but was surprised at the amount of water it held. *Some of the wood was okay and certainly a biatch to get off, other wood (6"x6" squares made up these hatches) was like wet sawdust and came right off.

My question is how "clean" do I have to get this surface before re-resining and putting on my new wood and overcoating with fiberglass cloth and resin???

Here is where I am at now and this last bit of wood is a real mutha. *




Am I good here, or do I need to keep sanding, I only have a pad sander so it is slow, or a chisel.

Franco, anyone????
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