/6 904 tranny stamping

Where is the tranny ID so I can reference it with the motor I plan on using?
The motor came from a 70 Dart. I will be putting it in a 68 Valiant. The tranny that came with the dart motor will probaby be sold since it has cables and my car has linkage driven parts. Te motor that is coming out has stamped 2463430-15. The motor going in is stamped 2806830-8.