From the October 30, 1983 OAG, which just happened to be on my desk just now.
1625, 1619, 1630 And 1671 All D9S
That is the extent of DL service on this date.
I have most of the OAGs from 1972 through the 1980s somewhere here. The 80s are readily available. I'll look tommorrow and let you know.
The day you stop learning is the day you should die.