I have an old fiberglass 60's v-hull that transom was worrying me more just because the age of the boat than anything. I had a 3/16 steel bracket made up and I installed it this afternoon and now the transom is super rock solid. If anyone is interested it is in this post.
http://forums.iboats.com/showthread.php?t=262977&page=1
http://forums.iboats.com/showthread.php?t=262977&page=1