Welcome, we have E35II, 1973. Definitely remove the chain plates. Both sides the bulkhead were rotten. You may have remove a wood cover plates. Check the stern plate...worth putting more fiberglass matt over it. Use white rubber mallet and do a sounding on every inch of the deck. There is a history rotten cores due to leaky deck fittings. That why we got a "great" deal on ours. The windows are known to leak. It has 40 year the caulking dries out. Do you have Atomic4, is it mid engine mount?
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