Dodge Ram Van Components in A Body?
I'd pull the engine and trans, use the engine and as much stuff attached to it as possible and probably just sell the transmission. Like
@Kern Dog said the transmission is most likely a 46RE or 46RH which is basically the same as an A-518; physically much larger than a 727 and won't fit an A-body transmission tunnel without some cutting. It's also not a very efficient transmission I know one member on here swapped an A-518 into his Duster and he only picked up 2-3 MPG compared to a 904 and I'm pretty sure that was all highway (city mileage stayed the same IIRC). The overdrive and lockup converter help highway mileage but in all other driving those transmissions take a lot of power to turn. It is a transmission intended for big trucks pulling heavy loads after all, not as much for high performance or fuel economy.