I haven't pulled back the carpet but I did look it over good from underneath, It is solid from what I can tell. Will know more tomorrow, I will post pics of what is inside the trunk and pics of the trim tag tomorrow.
I paid close to that for my 64 Valiant. It needed rear floor pans which I have already replaced and other now small rust repairs. The car had sat up since 1982 but I got it runnin very easily and drove it for a couple months earlier this year. But yours is a Barracuda. Even no engine, you did really good.