904 identification

V8 904 (999 versions with locking converters starting in 1978) could be had in light trucks and vans.
I'm not a numbers guy. If you go to the web site My Mopar you can find that information that lists year and what it was used in by the number found stamped on the pan rail about under the shifter shaft on the case.
If the seller will look for that number you will know just where it came from.