Hi Einar,
Sorry to hear you don't get too many answers here. Lots of knowledgeable folks here. Don't give up on us.
Appears to be an '86 Diplomat, Gran Fury, 5th Avenue 904 from behind a 318.
Here's a link for trans. #s-

http://mymopar.com/downloads/transguide.pdf

4412001 is the # (at the bottom of the page). Also has a picture of a 727 and 904 side-by-side.

Good luck.


Tim