Leaking transmission

I think the convertor drainback checks started in 66.
So if the TC pukes 1/2 it's fluid back into the 904case,well,you know there' not a lot of extra room in there! And OP's Dart is only a 106wb IIRC. And it's got slanty bars in it. And probably 13's. And maybe the floor was not level.
So I don't know.
lol
It happened to me once, and I remembered it, that's all