Re: 1975 Grampian 28 Engine Mount Failure
Last G28 I surveyed was a 1978 and it had a hollow FRP bed taped to the hull.
No wood core.
Grampians are not known for consistency of build so you can't really go by that.
Drill a 1/4" and probe with a metal coat hanger, you'll soon find out if anything is in there. Or as Faster says post a few photos and we should be able to tell you
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