My 1978 18 got a new raised foam transom from the inside. I will attempt to post photos.
http://i262.photobuck 
[image]The aft decks were removes as was the well.
http://s262.photobucket.com/albums/i...ruz/th_sc3.jpg[/image]
[image]The foam is not as rigid as plywood so some additional structure inside was needed.
http://s262.photobucket.com/albums/i...ruz/th_sc5.jpg[/image]
et.com/albums/ii113/keyscruz/sc.jpg
The boat is now mostly back together. It has an etec 150 and it survived itsfirst outing into rough water with no signs of stress.