Duky, I don’t know the pound weight of a kit body, but I feel comfortable saying that a reasonably healthy man could lift one corner without difficulty. If you have all the bolts out , it’s possible that the builder used some type of caulking to seal the body/pan joint and this may be holding the two sections together. Try using a wide flat tool ,like a putty knife, or maybe something a little stronger, to seperate them. Be VERY GENTLE. the fiberglass flanges will break if too much force is applied.
Perhaps someone who has actually done this will respond with possible ”hidden bolt” locations.