Just to add to this old topic; !!!
My boat is a 1964 woodie which someone or some people have redecked and painted all over; blue hull and deck; with white inner hull and remaining surfaces. The only varnished part is the tiller and the spinaker pole! The blue painted desk is very rough and may not even be marine ply, I guess.
My ambition is to remove all the white paint from the inside of the boat, the seats and thwarts, strip the deck down to the wood and varnish the upper and inner surfaces.
The hull was originally red; i can tell because when scraped it reveals the red below. There must be a considerable amount of paint on the boat, and much of it not even marine paint.
If faced with this problem, where would you start? The whole boat seems to be structurally OK.