transom and other stuff

My '73 V-20 CC has had its original transom repaired at some point before I bought it. I cant really tell the integrity of it but it makes me nervous going out in rough seas on Lake Ontario. I have a feeling the repair was a bandaid to the rot problem. someone bolted (both sides) a 3/16" sheet of stainless steel to the transom. Bolted through. If I lift my outboard (Yam. 150) and grab the prop for leverage, the transom does give a little. I'm not sure if any give at all is bad news!!
about a month ago, you guys set me up in the gallery so I can post some pics, but as soon as you did, got blasted with more snow so no pics. We've got nice weather now, I can take some pics and you guys can give me your opinions. My guess is it's new transom time. This kills me, fishing season starts in 1 week!!!
Damn, what to do. bag the year of boating to fix it or go for it.

Mike