RE: Marine trader hollow stringers
** Yep, they are as hollow as the keel, About 3 inches of mahogany, on top 2 inches on the bottom, plywood on the side and filled with solid air in the middle. Not to worry the*strength is in the glass. At least that is what I found on my 1977, 40 foot*sedan M/T.* You will most likely find two heavey red & black wires going thru the engine room forward bulkhead just inside the right inner stringer. They go forward to the anchor locked, for a winch I presume. There are also extra unused wires in the harness up to the flybridge so you won't have to run any for extra electronics.
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